Super Milk Thistle X [Discontinued] by Integrative Therapeutics

POSSIBLY EFFECTIVE

• Dyspepsia. Oral artichoke leaf extract may improve symptoms in patients with functional dyspepsia or dyspepsia associated with biliary disease. Details: Several clinical trials in patients with functional dyspepsia or dyspepsia associated with biliary disease show that taking artichoke leaf extract can reduce symptoms such as nausea, vomiting, flatulence, and abdominal pain. Improvement seems to occur after 2 to 8 weeks of treatment (2056,11429,12208). The validity of some of this evidence is limited by a small sample size (2056) or lack of a control group (11429). However, a higher-quality clinical trial in patients with mild dyspepsia shows that taking artichoke leaf extract 640 mg three times daily for 6 weeks improves overall symptom and quality of life scores. Specifically, patient ratings for flatulence, feelings of fullness, and early satiety were reduced when compared with placebo. Further, for every 12 patients treated with this extract over placebo, one additional patient reported markedly or completely improved symptoms (12208). Some studies have used a specific extract called ALE LI 220 (Hepar-SL forte, Serturner Arzneimittel GmbH) at doses ranging from 320-640 mg three times daily for up to 8 weeks (2056,12208). Another study has used a different artichoke leaf extract (Cynara SL, Lichtwer Pharma) at a dose of 320-640 mg daily for 2 months (11429). Some clinical research has also assessed artichoke extract in combination with ginger extract. Results show that taking 2 capsules of a specific product containing artichoke leaf extract 100 mg and ginger extract 20 mg (ProDigest, Indena) daily for 4 weeks markedly or completely improves symptoms such as nausea, fullness, pain, and bloating in about 1.5-fold more patients with functional dyspepsia when compared with placebo (91474).
• Hyperlipidemia. Most research shows that oral artichoke lowers cholesterol and triglyceride levels in patients with hyperlipidemia. However, frozen artichoke juice does not appear to have these effects. Details: Multiple meta-analyses and clinical studies in patients who are either healthy or have hyperlipidemia, nonalcoholic fatty liver disease, or pre-obesity show that taking artichoke leaf extract or concentrated artichoke juice capsules daily for 4-24 weeks reduces total cholesterol by 13-18 mg/dL, low-density lipoprotein (LDL) cholesterol by 15-17 mg/dL, and triglycerides by 9-18 mg/dL, but does not increase high-density lipoprotein (HDL) cholesterol, when compared with placebo (104132,108713,111560,111564). While the five studies including non-hyperlipidemic patients in one of these analyses reported mixed results, all four of the studies evaluating artichoke leaf extract in patients with hyperlipidemia showed significant reductions in total cholesterol and LDL cholesterol when compared with placebo (104132). Additionally, a dose-response analysis suggests that baseline cholesterol levels are a stronger predictor of benefit than dose and treatment duration (108713). The validity of these findings is limited due to the high heterogeneity of studies included in meta-analyses. Another clinical study in patients with mild hypercholesterolemia shows that taking artichoke extract 250 mg twice daily for 8 weeks decreases LDL cholesterol by about 11% and increases HDL cholesterol by about 10% when compared with placebo (91478). Other formulations have also been evaluated, including cynarin, a constituent of artichoke, and artichoke juice. Some older, small clinical studies suggest that taking cynarin 20 mg three times daily for 2-7 months reduces total cholesterol and triglyceride levels when compared to baseline in patients with hypercholesterolemia and/or hypertriglyceridemia (52222,52223,52236). However, cynarin does not appear to reduce cholesterol levels in patients with familial type II hyperlipoproteinemia (1424). In patients with hyperlipidemia, consuming frozen artichoke juice 20-30 mL daily for 6-12 weeks does not appear to reduce total or LDL cholesterol levels and may even increase triglyceride levels (52216,52234). Artichoke leaf extract has also been evaluated in combination with other ingredients. Clinical research shows that taking a product containing red yeast rice extract, artichoke leaf extract, and other ingredients (Limicol, Laboratoire Lescuyer) 3 or 6 tablets daily for 4-16 weeks decreases LDL cholesterol by 14% to 21% in patients with hyperlipidemia. However, the red yeast in this product contains monacolin K (lovastatin), which likely contributed to the cholesterol-lowering effect (89451,89452,89454). Another specific product (Vazguard; Indena SpA), containing artichoke leaf extract (Indena SpA) 100 mg and bergamot phytosome 600 mg, has also shown benefit in patients with mild hypercholesterolemia when taken twice daily for 2 months (108712). However, it is unclear if this effect is due to artichoke leaf, bergamot, or the combination.

INSUFFICIENT RELIABLE EVIDENCE to RATE

• Biliary disorders. Although there has been interest in using oral artichoke for various biliary disorders, including for the treatment of cholestasis or prevention of gallstones, there is insufficient reliable information about the clinical effects of artichoke for these conditions.
• Diabetes. Several small clinical studies suggest that oral artichoke extract may slightly reduce fasting blood glucose, but may not improve glycated hemoglobin (HbA1c) or other measures of glycemic control, in patients with diabetes. Details: A meta-analysis of 9 small clinical trials shows that taking artichoke leaf extract for 8-12 weeks reduces fasting blood glucose by around 5 mg/dL, but does not improve HbA1c, insulin levels, or markers of insulin resistance, when compared with placebo (105768). The generalizability of these findings to patients with diabetes is limited; only 2 of the 9 studies specifically enrolled patients with diabetes. The other studies included patients who were overweight or with liver disease, hyperlipidemia, or metabolic syndrome. In contrast, a post-hoc analysis of clinical research in overweight adults at risk for developing diabetes shows that taking a specific artichoke leaf product (Altilix, Bionap S.r.l.) 50 mg daily for 6 months reduces HbA1c by around 0.9% and improves measures of insulin resistance and beta-cell function when compared with placebo (111564).
• Hangover. It is unclear if oral artichoke extract is beneficial for the prevention of hangover. Details: A small clinical study in healthy adults shows that taking artichoke extract 960 mg immediately before and after alcohol consumption does not prevent alcohol-induced hangover when compared with placebo (11774).
• Hepatitis C. It is unclear if oral artichoke is beneficial in patients with hepatitis C. Details: One small clinical study in patients with chronic hepatitis C shows that taking artichoke leaf extract 3200 mg daily for 12 weeks does not normalize liver enzyme levels or reduce viral load when compared to baseline. Although symptoms such as fatigue, abdominal discomfort, and joint problems appear to improve in the first 4 weeks, the improvement is not maintained over 12 weeks (91475). However, another small clinical study shows that drinking a tea infusion of wild artichoke three times daily for 3 months normalizes liver enzymes and serum virus levels in 12 of 15 patients with hepatitis C (97717). The validity of these findings is limited by the lack of a control group.
• Hypertension. Analyses of small clinical studies suggest that oral artichoke may slightly reduce blood pressure in patients with hypertension; however, individual study results are conflicting, and the improvements in blood pressure may not be clinically significant. Details: Evidence regarding an association between artichoke consumption and hypertension is conflicting (91477,104133,105767,111561). Two meta-analyses include many of the same studies yet reach contradictory conclusions. One meta-analysis of 8 small clinical trials shows that taking artichoke leaf extract, powder, or juice for 8-12 weeks does not reduce systolic blood pressure (SBP) or diastolic blood pressure (DBP). However, subgroup analysis in patients with documented hypertension shows that artichoke reduces SBP by around 3 mmHg and DBP by around 2 mmHg when compared with placebo (105767). In contrast, another meta-analysis of 7 small clinical trials shows that taking artichoke 50-2700 mg daily for 4-12 weeks reduces SBP by about 2 mmHg and DBP by about 1.5 mmHg. Subgroup analysis shows that the greatest reductions in SBP and DBP occur in doses of 500 mg daily or less, at durations longer than 8 weeks, and in patients under 50 years old (111561). Discrepancies between the results of the meta-analyses with overlapping studies may be due to the former meta-analysis including artichoke supplementation in combination with other ingredients, while the latter meta-analysis focused on artichoke supplementation alone.
• Irritable bowel syndrome (IBS). It is unclear if oral artichoke leaf extract is beneficial in patients with IBS. Details: Some observational research in patients with IBS has found that taking a specific artichoke leaf extract (Hepar-SL forte, Serturner Arzneimittel GmbH) 640 mg three times daily for 6 weeks is associated with reductions in abdominal pain, cramping, bloating, flatulence, and constipation when compared to baseline (2562). Also, a small clinical study in patients with IBS shows that taking a different specific artichoke leaf extract (Cynara SL, Lichtwer Pharma) 320-640 mg daily for 2 months reduces the incidence of IBS symptoms in patients with dyspepsia by about 26% when compared to baseline. Patients taking this extract also had improved quality of life (15204). The validity of these findings is limited by the lack of a control group.
• Metabolic syndrome. It is unclear if oral artichoke leaf extract is beneficial in patients with metabolic syndrome. Details: A small clinical trial in patients with metabolic syndrome shows that taking artichoke leaf extract 1800 mg daily for 12 weeks does not improve fasting blood glucose, insulin resistance, total cholesterol, low-density lipoprotein (LDL) cholesterol, high-density lipoprotein (HDL) cholesterol, or blood pressure when compared with placebo. However, taking artichoke extract does reduce triglycerides by around 27 mg/dL when compared with placebo (100935).
• Nausea and vomiting. Although there has been interest in using oral artichoke for nausea and vomiting, there is insufficient reliable information about the clinical effects of artichoke for this purpose.
• Nonalcoholic fatty liver disease (NAFLD). It is unclear if oral artichoke leaf extract is beneficial in patients with NAFLD. Details: Meta-analyses of 12 clinical studies in adults with a variety of metabolic disorders, including NAFLD, show that taking artichoke 50-2700 mg daily for 4-24 weeks reduces alanine aminotransferase (ALT) and aspartate aminotransferase (AST) when compared with placebo (111560,111563). These effects are greater for ALT in trials lasting 8 weeks or longer and for AST at doses over 500 mg daily (111563). The validity of these findings is limited by significant heterogeneity among the included studies. A small clinical trial in patients with NAFLD shows that taking a specific artichoke leaf extract (Cynarol, Niak Pharmaceuticals), standardized to contain cynarin 2%, as 200 mg three times daily for 2 months improves NAFLD severity, reduces liver size, and increases hepatic vein flow when compared with placebo. The severity of NAFLD improved in 82% of patients taking artichoke, compared with 5% taking placebo. NAFLD severity did not worsen in any patients taking artichoke, compared with 27.5% of those taking placebo. Serum levels of liver transaminases, total bilirubin, and lipids were also improved with artichoke when compared with placebo (100934). However, the validity of these findings is limited by inappropriate randomization, the use of a per-protocol analysis, and significant differences between groups at baseline. Artichoke leaf extract has also been evaluated in combination with conventional therapies. A clinical trial shows that taking metformin 500 mg twice daily and/or vitamin E 400 IU once daily along with a specific artichoke leaf extract (Tishoke; Goldaru Company) 400 mg twice daily, providing 40 mg chlorogenic acid daily, for 12 weeks improves NAFLD severity and reduces liver size when compared with baseline. However, these improvements were similar to those seen in patients taking metformin with vitamin E. After 12 weeks, the number of patients with no fat accumulation (steatosis grade 0) increased by 23% in the artichoke and metformin group, 17% in the artichoke and vitamin E group, and 10% in the metformin and vitamin E group (108714)
• Obesity. A meta-analysis of several small clinical studies suggests that oral artichoke extract may slightly reduce waist circumference, but not body weight or body mass index (BMI), in patients who are overweight or obese. Details: A meta-analysis of 10 small clinical trials shows that taking artichoke leaf extract, powder, or juice for 8-12 weeks reduces waist circumference by 1.11 cm, but does not improve body weight or BMI, when compared with placebo (105766). The generalizability of these findings to patients who are overweight or obese is limited by the fact that only 3 of the 10 trials specifically enrolled patients because they were overweight. Other studies evaluated patients with liver disease, metabolic syndrome, diabetes, hyperlipidemia, or hypertension. In contrast, a post-hoc analysis of clinical research in adults with overweight shows that taking an artichoke leaf supplement (Altilix, Bionap S.r.l.) 150 mg daily for 6 months reduces body weight by around 2.3 kg but does not improve waist circumference when compared with placebo (111564).
• Osteoarthritis. Although there has been interest in using oral artichoke for osteoarthritis, there is insufficient reliable information about the clinical effects of artichoke for this purpose. More evidence is needed to rate artichoke for these uses.

(Read more about ARTICHOKE)

INSUFFICIENT RELIABLE EVIDENCE to RATE

• Constipation. Although there has been interest in using oral dandelion for constipation, there is insufficient reliable information about the clinical effects of dandelion for this purpose.
• Dyspepsia. Although there has been interest in using oral dandelion for dyspepsia, there is insufficient reliable information about the clinical effects of dandelion for this purpose.
• Flatulence. Although there has been interest in using oral dandelion for flatulence, there is insufficient reliable information about the clinical effects of dandelion for this purpose.
• Heart failure. Although there has been interest in using oral dandelion for its diuretic effects in patients with heart failure, there is insufficient reliable information about the clinical effects of dandelion for this purpose.
• Joint pain. Although there has been interest in using oral or topical dandelion for joint pain, there is insufficient reliable information about the clinical effects of dandelion for this purpose.
• Postoperative pain. It is unclear if topical dandelion is beneficial in patients with pain after jaw surgery. Details: A small clinical study in patients undergoing maxillofacial surgery shows that topical application of dandelion combined with borneol one time on the day of surgery and twice daily on the first and second days after surgery for 30 minutes does not reduce maxillofacial pain when compared with cold compresses or either ingredient alone (112484). The validity of this finding is limited by concurrent use of opioid analgesic and nonsteroidal anti-inflammatory medications.
• Postoperative swelling. It is unclear if topical dandelion is beneficial in patients with swelling after jaw surgery. Details: A small clinical study in patients who underwent maxillofacial surgery shows that topical application of dandelion combined with borneol one time on the day of surgery and twice daily on the first and second days after surgery for 30 minutes modestly reduces facial swelling and improves mouth opening abilities when compared with cold compresses or borneol alone (112484). It is unclear whether this effect is due to dandelion, borneol, or the combination.
• Tonsillitis. It is unclear if oral dandelion is beneficial in patients with tonsillitis. Details: One small clinical study in patients with acute purulent tonsillitis shows that eating soup containing dandelion (pugongying soup) daily for 3 days along with benzylpenicillin sodium 640,000 units daily improves recovery when compared with placebo plus benzylpenicillin sodium. Recovery rates were 36% with the dandelion-containing soup compared to 10% with placebo (18292).
• Urinary tract infections (UTIs). Oral dandelion has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: A small clinical study in females with recurrent UTIs shows that taking a specific combination of dandelion root and uva ursi leaf extracts three times daily for 1 month reduces the risk of UTI recurrence when compared with placebo at 12-month's follow-up. For every 5 patients treated with this combination over placebo, one additional UTI was prevented (1932). In this combination, uva ursi is used for its antibacterial properties and dandelion is used to increase urination. However, this combination is not recommended for extended use because uva ursi may be unsafe when used long-term. Another small clinical study in premenopausal females with acute, uncomplicated lower UTIs shows that taking a combination product containing dandelion extract 50 mg, D-mannose, prebiotics, arabinogalactan, and astragalus root extract twice daily for five days, along with phenazopyridine and alkylating agents as conventional therapy, improves UTI symptoms and bacteriuria when compared with placebo plus conventional therapy (111757). It is unclear if these effects are due to dandelion, other ingredients, or the combination. More evidence is needed to rate dandelion for these uses.

(Read more about DANDELION)

POSSIBLY EFFECTIVE

• Atopic dermatitis (eczema). Some clinical research suggests that topical licorice seems to improve symptoms of atopic dermatitis. Details: Applying gel formulations containing 1% or 2% licorice root extract three times daily for 2 weeks seems to reduce erythema by 35% to 61%, edema by 57% to 84%, and itching by 44% to 73%. The 2% gel seems to be more effective than the 1% gel (59732).
• Canker sores. Some clinical research suggests that topical licorice patches and mouth rinses seems to reduce ulcer size and pain in patients with recurrent aphthous stomatitis. Details: Clinical research shows that applying an oral patch containing licorice 0.015-0.229 mg/kg for 16 hours each day for 8 days does not affect ulcer healing time, but reduces ulcer size and post-stimulus pain, when compared with placebo (59769). A small clinical study also shows that applying bioadhesive hydrogel patches containing 1% licorice extract reduces the pain, as well as the diameter of necrosis and inflammatory halo of recurrent canker sores, when compared to baseline (59781). Mouth rinses containing licorice have also been used. One clinical study shows that swishing a diphenhydramine and 5% licorice extract solution around the mouth for about 3 minutes four times daily until the sores have healed reduces the average time to healing by 1.5 days when compared to a solution containing diphenhydramine alone. Pain was reduced by up to 69% more in those using licorice extract (104564). Another small clinical study shows that gargling with licorice extract four times daily for 2 days has a large beneficial effect on pain and ulcer size when compared with using a placebo gargle. The licorice extract was made by boiling licorice root 40 grams in one liter of water for 30 minutes and cooled (110319). In addition, preliminary clinical research shows that gargling with warm water containing deglycyrrhizinated licorice powder 200 mg four times daily for 7 days improves pain in 75% of patients by day one and results in complete healing in 75% of patients by day three (59857).
• Endotracheal intubation-related adverse effects. Some clinical research suggests that using licorice as a gargle or lozenge prior to endotracheal intubation can reduce adverse effects like sore throat and cough. Details: A meta-analysis of 5 clinical trials in patients undergoing elective surgical procedures shows that topical use of licorice, either as a gargle or lozenge, prior to endotracheal intubation reduces the risk for sore throat by 56% and reduces the risk for cough by 39% when compared with a control group at 24 hours post-extubation (100985). One clinical study included in this analysis shows that sucking on a single lozenge (Sualin, Hamdard Pharma) containing licorice extract 97 mg beginning 30 minutes prior to intubation reduces the risk for cough immediately after extubation by 56% when compared with a sugar candy lozenge. However, it doesn't seem to reduce cough at 30 minutes, 12 hours, or 24 hours post-extubation. This lozenge also appears to reduce the risk for sore throat by about 32% at 12 and 24 hours post-extubation, but not immediately or 30 minutes after extubation (25670). Additional clinical studies included in the meta-analysis show that gargling with fluid prepared with licorice 0.5 grams for at least one minute beginning 5 minutes prior to endotracheal intubation reduces the incidence and severity of post-extubation sore throat and coughing when compared with a water control (26464,59793).

INSUFFICIENT RELIABLE EVIDENCE to RATE

• Acne. Topical licorice has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: Clinical research in patients with mild to moderate acne associated with mask wearing shows that topical application of a combination of licorice root extract 0.3%, calendula 4%, and snail secretion filtrate 40% (AI complex) to the face twice daily for 12 weeks modestly reduces inflammatory, but not non-inflammatory or total, acne lesions when compared with placebo. There was no difference in overall treatment success, defined as at least almost clear skin or a large improvement (110322). It is unclear if any benefits are due to licorice, other ingredients, or the combination.
• Addison disease. Although there has been interest in using oral licorice for Addison disease, there is insufficient reliable information about the clinical effects of licorice for this condition.
• Adrenal insufficiency. Although there has been interest in using oral licorice for adrenal insufficiency, there is insufficient reliable information about the clinical effects of licorice for this condition.
• Allergic rhinitis (hay fever). It is unclear if using a licorice-containing nasal irrigation suspension improves symptoms in patients with allergic rhinitis. Details: A clinical study in patients with allergic rhinitis shows that using a nasal irrigation suspension containing licorice extract 900 mg daily for 1 month improves symptoms such as nasal blockage, rhinorrhea, sneezing, postnasal discharge, and olfactory disturbance when compared with baseline (108569). Although the study also utilized mometasone 2 mg nasal spray and isotonic saline nasal irrigation as comparators, symptom improvement was observed in all three groups, and there was no statistical comparison of outcomes between groups.
• Antipsychotic-induced hyperprolactinemia. Oral licorice has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: Preliminary clinical research in females with risperidone-induced hyperprolactinemia shows that taking a combination of licorice and peony (Peony-Glycyrrhiza Decoction; PGD) 45 grams daily for 4 weeks reduces prolactin levels to a similar extent as bromocriptine (59775). However, another study shows that taking the same product at the same dose for 16 weeks has no effect on prolactin levels in females with antipsychotic-induced hyperprolactinemia when compared with placebo. Although the prolactin-related adverse event questionnaire total score was moderately improved, there was no effect on clinically meaningful symptoms or menstrual resumption (97219). Both studies show no effect on psychotic symptoms (59775,97219). Preliminary clinical research in male patients with antipsychotic-induced hyperprolactinemia shows that taking an herbal extract containing licorice and peony (shakuyaku-kanzo-to) 2.5 grams three times daily reduces prolactin levels after 4 weeks, but does not have a significant effect on prolactin levels 4 weeks after treatment cessation (59907).
• Bleeding. Topical licorice might reduce bleeding when used in combination with other ingredients; its effect when used alone is unclear. Details: Some preliminary clinical research shows that topically applying 4 mL of a specific product (Ankaferd Blood Stopper, Mefar Ilaç Sanayi A.S.) containing licorice, Alpinia, thyme, stinging nettle, and common grape vine reduces bleeding, but does not improve the surgical time for episiotomy repair, when compared with saline (31010). Other preliminary clinical research shows that ampules of this same product placed in empty alveolus for up to 20 minutes reduces bleeding in postsurgical dental patients with increased bleeding tendency (31002).
• Cancer-related pain. It is unclear if oral licorice is beneficial for pain in patients with cancer. Details: Preliminary clinical research shows that taking a 1:1 combination of licorice root and peony root, along with a Taiwanese tonic vegetable soup comprised of lily bulb, lotus seed, and jujube fruit, reduces pain levels in terminal cancer patients when compared with patients consuming only the soup or the regular hospital diet (59770).
• Chronic fatigue syndrome (CFS). Although there has been interest in using oral licorice for CFS, there is insufficient reliable information about the clinical effects of licorice for this condition.
• Colic. Although there has been interest in using oral licorice for colic, there is insufficient reliable information about the clinical effects of licorice for this condition.
• Coronavirus disease 2019 (COVID-19). Oral licorice has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: A small clinical study in patients hospitalized in Egypt with moderate COVID-19 shows that administering oral licorice extract 300 mg (standardized to contain glycyrrhizin 60 mg) once daily and Boswellia serrata extract 300 mg twice daily for 14 days, along with following an institution-based COVID-19 treatment protocol, may modestly improve mortality and time to recovery when compared with patients receiving the standard protocol alone. The standard treatment protocol included acetaminophen, azithromycin, vitamin C, zinc, and enoxaparin (108579). It is unclear if any effect is due to licorice, Boswellia serrata, or the combination.
• Dental caries. It is unclear if oral licorice is beneficial for the prevention of dental caries. Details: One clinical study in adults shows that swishing 15 mL of a solution containing licorice extract 1% once nightly before bed for 5 days may reduce the acid production of cavity-causing bacteria, which may modestly reduce cavity risk, when compared with using a saline solution (108567). The validity of this study is limited by the short duration of treatment and follow-up.
• Dental plaque. It is unclear if licorice toothpaste or mouthwash is beneficial for reducing plaque. Details: Preliminary clinical research shows that using 0.25% or 0.50% glycyrrhizin-containing toothpaste twice daily does not reduce the amount of plaque, gingivitis, or bleeding in patients with proper dental hygienic measures when compared with the same toothpaste without glycyrrhizin (59812). Also, other preliminary clinical research shows that using glycyrrhizin-containing mouthwash for 3 days does not significantly reduce plaque levels (59855).
• Depression. It is unclear if adding oral licorice to standard treatment is beneficial for improving depression. Details: A very small, nonblinded clinical study in hospitalized adults with major depressive disorder shows that adding licorice extract 1400 mg daily, standardized to glycyrrhizin 7% to 8%, to standard treatment for 2 weeks improves depression rating scores when compared with baseline, although these improvements were numerically similar to those seen with standard treatment alone. Patients in the treatment group also took oral magnesium citrate 300 mg daily to prevent magnesium depletion. The validity of this finding is limited due to the small size of the study, short duration of treatment, and unclear reporting (108575).
• Diabetes. Although there has been interest in using oral licorice for diabetes, there is insufficient reliable information about the clinical effects of licorice for this condition.
• Dry mouth. It is unclear if rinsing the mouth with licorice is beneficial for dry mouth in people on hemodialysis. Details: Preliminary clinical research in hemodialysis patients with dry mouth shows that rinsing with a licorice mouthwash containing 8.34 grams of licorice concentrate per 500 mL of water with every meal for 10 days does not affect salivary flow rate, but reduces subjective feelings of dry mouth by about 28%, when compared with a water-based mouthwash and control group (97220).
• Dysmenorrhea. It is unclear if oral licorice is beneficial for reducing pain. Details: Preliminary clinical research shows that taking a syrup providing licorice extract 750 mg twice daily for the first 5 days of the menstrual cycle reduces pain as effectively as ibuprofen 400 mg every 8 hours in patients with moderate or severe dysmenorrhea (104558).
• Dyspepsia. Oral licorice might improve symptoms of dyspepsia when used in combination with other ingredients; its effect when used alone is unclear. Details: Various combination products manufactured by Steigerwald Arzneimittelwerk GmbH have been evaluated for dyspepsia. Two specific combination products containing licorice root (Iberogast; STW-5-S) seem to improve symptoms of dyspepsia. The combinations include licorice plus milk thistle, peppermint leaf, German chamomile, caraway, celandine, angelica, and lemon balm either with (Iberogast) or without clown's mustard plant (STW-5-S) 1 mL three times daily for 4 weeks (19532). A meta-analysis of studies using the Iberogast product shows that taking 1 mL orally three times daily over a period of 4 weeks reduces severity of acid reflux, epigastric pain, cramping, nausea, and vomiting when compared with placebo (13089). Also, using a preparation containing clown's mustard plant, German chamomile, peppermint, caraway, licorice, and lemon balm (STW 5-II) 1 mL three times daily for up to 12 weeks improves dyspepsia symptoms in 40% more patients when compared with placebo (12724).
• Familial Mediterranean fever. It is unclear if oral licorice is beneficial for familial Mediterranean fever. Details: Preliminary clinical research shows that taking a combination of licorice, andrographis, Siberian ginseng, and schisandra (ImmunoGuard, Inspired Nutritionals) four tablets three times daily for one month reduces the duration, frequency, and severity of attacks of familial Mediterranean fever in children when compared with placebo (12382). It is unclear if these effects are due to licorice, other ingredients, or the combination.
• Helicobacter pylori. It is unclear if oral licorice is beneficial for Helicobacter pylori eradication. Details: Some preliminary clinical research shows that adding licorice (D-Reglis, Iran Darouk Pharmaceutical Co.) 380 mg twice daily to conventional clarithromycin-based triple therapy for 14 days improves eradication rate by an additional 21% when compared with conventional treatment alone. However, any additional benefit might be limited to patients with peptic ulcer disease (97221). Other preliminary clinical research shows that taking a combination of licorice extract 100 mg and Lactobacillus paracasei HP7 in 150 mL of fermented milk daily for 8 weeks does not increase eradication rates when compared with fermented milk alone, although it may improve gastrointestinal symptom scores, decrease the gastric load of Helicobacter pylori, and improve some measures of inflammation when compared to baseline (100984).
• Hepatitis. Evidence for the use of intravenous licorice in the management of hepatitis B and C is mixed. Details: In some preliminary clinical research, a specific glycyrrhizin-containing intravenous preparation (Stronger Neominophagen C, Minophagen Pharmaceutical Co. Ltd.) appears to reduce mortality due to viral hepatitis by about 50% (3250). Other clinical research suggests that this same product reduces serum alanine aminotransferase (ALT) in hepatitis C patients but does not improve hepatitis C virus (HCV)-RNA levels (3247,59712,59721,59920). When used long-term, this preparation seems to reduce the risk of hepatocellular carcinoma in hepatitis C patients when compared to long-term use of other supplements, such as vitamin K (59905). This product has been used in various doses: 40 or 100 mL, containing 2 mg glycyrrhizin, 1 mg cysteine, and 20 mg of glycine per mL of solution, administered daily for 4-8 weeks, followed by 40 or 100 mL 2-7 times weekly for 2-16 weeks, has been used (3250,59905,59915); 40-120 mL diluted in 100 mL of 5% glucose solution and administered three times weekly for 4 weeks (59712,59721); 100 mL, which contained 200 mg glycyrrhizin, administered undiluted six times weekly for 4 weeks (59721); or 60 mL administered three times weekly for 16 weeks (59920). Other research shows that this preparation reduces ALT, aspartate aminotransferase (AST), and gamma-glutamyl transpeptidase (GGT) in patients with hepatitis B virus (59915). Oral licorice has not been evaluated for this purpose.
• Hypercholesterolemia. It is unclear if oral licorice is beneficial for improving cholesterol. Details: Preliminary clinical research shows that taking licorice root extract 0.1 grams daily for one month reduces plasma total cholesterol levels by 5%, plasma low-density lipoprotein (LDL) cholesterol levels by 9%, and plasma triglyceride levels by 14% when compared with baseline in patients with moderate hypercholesterolemia (59725). The validity of these findings is limited by the lack of a comparator group.
• Hyperkalemia. It is unclear if oral licorice is beneficial for reducing potassium levels. Details: Some clinical research in adults with diabetes and hypoaldosteronism suggests that taking glycyrrhizin 150 mg daily decreases potassium levels when compared with calcium polystyrene sulfonate (59897). Also, one very small clinical study in patients with anuria shows that taking glycyrrhetinic acid 1 gram daily for 2 weeks seems to decrease plasma potassium, but does not improve blood pressure, when compared with placebo (59723).
• IgA vasculitis. Oral licorice has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: A small retrospective study in patients aged 5-36 years with newly diagnosed IgA vasculitis shows that taking compound glycyrrhizin (Eisai Pharmaceutical Co, Ltd) three times daily along with loratadine, calcium, vitamin C, rutin, and other unspecified conventional treatments is associated with an improvement in cutaneous purpura symptoms and time to symptom regression when compared with placebo. After 1 month, the rate of complete resolution and time to regression in the treatment group was 82% and 5 days, respectively, compared with 65% and 8 days, respectively, in the placebo group. Compound glycyrrhizin contained glycyrrhizin, glycine, and methionine and was dosed by age, with a dose of 25 mg daily in those 12 years or younger and 50 mg daily in those over 12 years (108580).
• Irritable bowel syndrome (IBS). Oral licorice has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: Preliminary clinical research shows that a formulation containing licorice root, slippery elm bark, lactulose, and oat bran daily for 2 weeks improves stool consistency and increases bowel movement frequency by 20% in individuals with constipation-predominant IBS when compared to baseline. Symptoms of abdominal pain, bloating, straining, and global severity might also be reduced (35462). The validity of these findings is limited by the lack of a comparator group. Additionally, it is unclear if any benefits are due to licorice, other ingredients, or the combination.
• Lichen planus. It is unclear if intravenous licorice is beneficial for lichen planus. Details: A very small clinical study shows that intravenous administration of 0.2% glycyrrhizin solution, 40 mL daily for 4 weeks, improves clinical symptoms of oral lichen planus in a greater percentage of patients with chronic hepatitis C when compared with dental cleaning (59903). There is no evidence suggesting that oral licorice is beneficial.
• Liver cancer. Although there has been interest in using oral or intravenous licorice preparations for liver cancer, there is insufficient reliable information about the clinical effects of licorice for this condition.
• Melasma. Topical licorice has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: Preliminary clinical research shows that applying a topical cream (Clariderm Clear, Stiefel Laboratories Inc.) containing 7% licorice, emblica, and belides twice daily for 60 days is as effective as a cream containing 2% hydroquinone for lightening the skin in patients with melasma (59824). It is unclear if this effect is due to licorice, other ingredients, or the combination.
• Menopausal symptoms. It is unclear if oral licorice is beneficial for reducing hot flash frequency or severity. Details: In one preliminary clinical study, taking licorice root extract 330 mg orally three times daily for 8 weeks modestly reduces the frequency of hot flashes by about 1.3 per day and the severity of hot flashes by about 40% when compared with placebo (94659). However, another preliminary clinical study shows that taking a specific licorice root extract (D-Reglis, Iran Darouk Pharmaceutical Co.) 650 mg orally daily for 90 days does not reduce the number or severity of hot flashes when compared to baseline (25694).
• Muscle cramps. It is unclear if oral licorice is beneficial for muscle cramps due to cirrhosis or hemodialysis. Details: Preliminary clinical research shows that taking a specific combination of licorice and peony (shakuyaku-kanzo-to) might reduce muscle cramps in patients with hepatic cirrhosis or in patients undergoing hemodialysis when compared to baseline (13550,13551,13552). This combination was taken as 6-7.5 grams daily in up to three divided doses for 2-4 weeks in two studies (13550,13552). In a third study, the combination was taken as 2.5 grams during hemodialysis with self-administration at the onset of muscle cramping (13551).
• Nonalcoholic fatty liver disease (NAFLD). It is unclear if oral licorice is beneficial for NAFLD. Details: A small clinical trial in females with NAFLD shows that taking licorice extract (Shirin Darou Company, Shiraz, Iran) 500 mg twice daily for 12 weeks improves some measures of liver health and glycemic control when compared with placebo. Modest improvements occurred in levels of alanine aminotransferase, as well as in measures of insulin resistance and severity of liver steatosis based on ultrasonographic evaluation. There were no effects on body mass index (BMI), plasma lipids, fasting blood glucose, or other liver enzymes. All patients were also given weight loss and healthy lifestyle advice (110320). Preliminary clinical research shows that taking licorice root extract 2 grams daily for 2 months reduces liver function enzyme levels in patients with NAFLD when compared to pre-treatment (59841). It is unclear if this reduction is clinically significant.
• Obesity. It is unclear if oral licorice is beneficial for weight loss. Details: Preliminary clinical research shows that taking a specific licorice flavonoid oil (Glavonoid) 300 mg daily for 8 weeks has no effect on weight or body fat when compared with placebo in obese patients (17727).
• Oral mucositis. It is unclear if oral or topical licorice is beneficial for the prevention or treatment of chemotherapy- or radiation-induced oral mucositis. Details: In patients with head and neck cancer undergoing chemoradiation, preliminary clinical research shows that using oral and topical licorice powder twice daily in addition to conventional treatments for 6 weeks reduces the overall incidence of mucositis and also reduces the risk of developing severe oral mucositis to 15.5%, compared with 20% in those using topical honey and 43% in those using conventional treatments alone. Licorice treatment consisted of yastimadhu powder 5 grams mixed in honey for topical application in the mouth, as well as yastimadhu capsule 500 mg twice daily orally (104562). A small clinical trial in patients with head and neck cancer and oral mucositis currently undergoing radiation therapy shows that applying a mucoadhesive film containing licorice to the upper lip mucosal surface four times daily for 4 weeks, in conjunction with standard oral care, improves pain scores, mucositis grading, and ulcer size when compared with placebo film (108572). The validity of this finding is limited due to the short duration of treatment and exclusion of patients with severe mucositis.
• Osteoarthritis. Although there has been interest in using oral licorice for osteoarthritis, there is insufficient reliable information about the clinical effects of licorice for this condition.
• Osteoporosis. Although there has been interest in using oral licorice for osteoporosis, there is insufficient reliable information about the clinical effects of licorice for this condition.
• Parkinson disease. It is unclear if oral licorice is beneficial for improving Parkinson disease symptoms. Details: A small clinical study in patients with Parkinson disease shows that taking licorice extract 136 mg (containing glycyrrhizin 12.14 mg, polyphenols 136 mcg, and flavonoids 2.6 mcg) in a 5 mL syrup twice daily for 6 months improves Parkinson symptoms, tremor, and overall daily activities when compared with placebo (102961).
• Peptic ulcers. Evidence for the use of oral licorice for peptic ulcers is mixed. Details: There is some evidence that taking 6-12 tablets each containing deglycyrrhizinated licorice 380 mg, bismuth subnitrate 100 mg, aluminum hydroxide gel 100 mg, magnesium carbonate 200 mg, sodium bicarbonate 100 mg, and powdered alder buckthorn bark 30 mg (Caved-S, Cedona) in up to three divided doses daily for 4-16 weeks might accelerate the healing of peptic ulcers (11312,11313). Some clinical research also shows that this product is as effective as carbenoxolone sodium (Biogastrone) when taken at doses of two tablets three times daily after meals for 4 weeks (59871). In contrast, taking deglycyrrhizinated licorice (Ulcedal, Cedona, and others) 450-1000 mg three to five times daily for 4-8 weeks or glycyrrhizinic acid-reduced licorice 760 mg three times daily for 6 weeks does not seem to reduce the need for medication, pain, burning, or other discomfort in patients with peptic ulcers when compared with placebo (59864,59865,59873,59874).
• Physical performance. It is unclear if oral licorice is beneficial for improving physical performance in older females. Details: A small clinical trial in healthy females 59 years and older shows that taking licorice flavonoid oil 300 mg orally daily for 16 weeks in addition to strength training does not improve walking speed or other measures of functional mobility when compared with strength training alone (102960).
• Polycystic ovary syndrome (PCOS). Oral licorice has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: Clinical research shows that taking licorice root extract 2250 mg daily along with Ceylon cinnamon, levant berry, St. John's Wort, peony, and tribulus for 3 months with lifestyle modification improves symptoms of PCOS, including a reduction in oligomenorrhea/amenorrhea by 33% and the number of days between menstrual cycles by 43 days when compared with lifestyle modification alone. Although conception rate increased 4-fold in the intervention group, live birth rate was similar between groups (97216). The effect of licorice alone for the treatment of PCOS is unknown.
• Prostate cancer. Although there has been interest in using oral licorice for prostate cancer, there is insufficient reliable information about the clinical effects of licorice for this condition.
• Psoriasis. It is unclear if topical licorice is beneficial for improving psoriasis symptoms. Details: Preliminary clinical research shows that using a topical cream containing licorice extract and milk proteins twice daily for 4 weeks does not reduce the duration of corticosteroid cream therapy in patients with palmar and/or plantar psoriasis, but may improve skin peeling, the area of skin affected, and some subjective symptoms, when compared with corticosteroid cream alone (59823).
• Systemic lupus erythematosus (SLE). Although there has been interest in using oral licorice for SLE, there is insufficient reliable information about the clinical effects of licorice for this condition.
• Tuberculosis. Although there has been interest in using oral licorice for tuberculosis, there is insufficient reliable information about the clinical effects of licorice for this condition.
• Urticaria. Oral licorice has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: A meta-analysis of clinical research in adults with chronic urticaria shows that taking compound glycyrrhizin, containing glycyrrhizin, N-acetyl cysteine, and glycine, as 50-75 mg three times daily along with desloratadine 5-8.8 mg daily for 4 weeks improves response rate, cure rate, and recurrence rate when compared with desloratadine alone (108571). However, most studies included in the meta-analysis were low quality, and all studies were conducted in China. Higher quality studies in other geographic locations are needed to confirm these findings.
• Vitiligo. It is unclear if the licorice constituent compound glycyrrhizin is beneficial for vitiligo. Details: A meta-analysis of 14 clinical studies in patients aged 3-68 years old with vitiligo shows that taking licorice constituent compound glycyrrhizin 25-75 mg 3 times daily for 2-6 months with standard treatment improves effectiveness, cure rate, and immune-mediated inflammatory markers when compared with standard treatment alone (112232). More evidence is needed to rate licorice for these uses.

(Read more about LICORICE)

POSSIBLY EFFECTIVE

• Diabetes. Oral milk thistle extracts of silymarin seem to improve glycemic control in patients with diabetes. Details: A meta-analysis of 7 small heterogeneous clinical trials in patients with type 2 diabetes shows that taking milk thistle containing silymarin 210-600 mg alone or with other ingredients daily for up to 6 months reduces fasting blood glucose and glycated hemoglobin when compared with control. Sub-group analyses suggest that studies conducted for less than 3 months seem to have a greater glycemic benefit than those lasting 3 months or longer. Furthermore, there was a greater glycemic benefit when milk thistle was used in combination with other natural ingredients (105054). Most studies in the analysis used silymarin in divided doses of 420-600 mg daily, while only one study used 200 mg daily (15102,63190,97626,105054). Additionally, a meta-analysis of 22 clinical studies in healthy adults and adults with diabetes or other medical conditions shows that taking milk thistle reduces fasting blood glucose by around 22 mg/dL, reduces glycated hemoglobin by 0.85%, and reduces fasting insulin by 3.8 mU/mL when compared with placebo or control (113987). Most of these studies were conducted in the Middle East, so it is unclear whether these results are generalizable to other geographic locations. Most studies of combination products have been conducted in Italy and involve a specific product (Berberol, PharmExtracta) containing milk thistle standardized to silymarin 105-210 mg with tree turmeric standardized to berberine 500-1000 mg (96141,105054). In addition to improving glycemic indices in patients with type 2 diabetes (105054), this product has shown glycemic benefit in patients with concomitant obesity and metabolic syndrome (97624) and in patients with type 1 diabetes (96142).

INSUFFICIENT RELIABLE EVIDENCE to RATE

• Acne. It is unclear if oral or topical milk thistle is beneficial in patients with acne when used alone or in combination with other treatments. Details: A small clinical trial in patients with acne vulgaris shows that taking a milk thistle extract standardized to silymarin 140 mg daily for 2 months does not improve acne severity based on the Global Acne Grading system scale when compared with doxycycline 100 mg daily, and silymarin is less effective than doxycycline when evaluated using the Acne Severity Index (ASI) scale. In addition, using silymarin in combination with doxycycline does not appear to be more effective than doxycycline alone (101160). There is also interest in using milk thistle topically for acne. A small quasi-experimental study in adults with mild to moderate acne suggests that applying silymarin 1.4% cream twice daily for 3 months improves global acne scores and appearance of acne when compared to baseline, but not when compared with biweekly salicylic acid chemical peels (113143). However, the interpretation of these results is limited by the use of subjective outcomes. Similarly, observational research in patients aged 12-25 years with mild-to-moderate acne suggests that applying a specific cream (Cleanance Comedomed, Pierre Fabre Dermo-Cosmetique) containing milk thistle fruit extract 25% twice daily for 8-12 weeks as initial or add-on therapy is associated with moderate improvements in acne scores when compared to baseline (111175). The interpretation of these results is limited by the lack of a comparator group. Further, most patients were also prescribed other skincare products or treatments. Topical milk thistle has also been evaluated in combination with other ingredients. A small open-label study conducted in Korea in adults with acne vulgaris shows that applying a specific topical product (Silymarin CF, Skinceuticals) containing silymarin 0.5%, vitamin C 15%, salicylic acid 0.5% and ferulic acid 0.5%, twice daily for 3 months moderately improves acne scores when compared to baseline (110488). A similar open-label study conducted in Brazil in adults with acne shows that applying a serum with this same combination and concentration of ingredients once daily for 12 weeks improves investigator's global assessment of acne severity, global lesion count, inflammatory and non-inflammatory lesions, post-inflammatory hyperpigmentation, skin clarity, skin tone evenness, and overall skin appearance and reduces skin surface oil when compared to baseline. Additionally, an open-label study conducted in the US and Germany in adults with acne shows that applying this same serum daily for 4 weeks in addition to prescription topical acne medications reduces investigator-assessed erythema, dryness, and scaling when compared to baseline (113985). In the aforementioned studies, it is unclear if these effects are due to milk thistle, other ingredients, or the combination. The validity of the studies is also limited by the lack of a comparator group.
• Alcohol-related liver disease. It is unclear if oral milk thistle is beneficial in patients with alcohol-related liver disease, as evidence is conflicting. Details: Some preliminary research shows that taking a milk thistle extract containing 70% to 80% silymarin (Legalon, Madaus GmbH) 420 mg orally daily for one month to 4 years improves some liver function tests (2613,2618,17228,63260,63339). Some studies also report improvements in liver histology and survival (2616,17228,63278). However, in other studies, taking a similar dose of the same product for 3 months to 2 years is not associated with any benefit over placebo (7321,7322,7355,63158). A meta-analysis of clinical research also shows that milk thistle extract does not reduce mortality or complications related to liver disease in patients with alcohol-related liver disease (63192). Reasons for the conflicting findings are unclear but might relate to the low methodological quality of many of these studies.
• Allergic rhinitis (hay fever). It is unclear if oral milk thistle is beneficial in patients with allergic rhinitis. Details: One preliminary clinical trial shows that taking a milk thistle extract of silymarin 140 mg orally three times a day plus cetirizine (Zyrtec) 10 mg daily for one month decreases the severity of allergic rhinitis symptoms when compared with placebo plus cetirizine (18105).
• Alzheimer disease. It is unclear if oral milk thistle is beneficial in patients with Alzheimer disease. Details: A small, single-blind clinical study in patients with Alzheimer disease shows that taking milk thistle 450 mg daily for 3 months improves scores on the Mini Mental State Exam when compared with placebo (113978). Other preliminary clinical research shows that taking a supplement containing a milk thistle extract of silymarin 150 mg in combination with ferulic acid, gamma-oryzanol, and apigenin orally twice daily for 3 months to 2 years may stabilize mental functioning in patients with Alzheimer disease when compared to baseline (63223). It is unclear if this effect is due to milk thistle, other ingredients, or the combination.
• Amanita mushroom poisoning. While an intravenous milk thistle constituent, silibinin, has been studied for treating Amanita mushroom poisoning, this product is not readily available in the U.S. Details: Preliminary evidence from uncontrolled studies shows that administering silibinin, a constituent of milk thistle, intravenously (IV) within 48 hours of Amanita phalloides (death cap) mushroom poisoning, followed by oral therapy, may lessen liver damage (2615,63293). However, silibinin is not readily available in the US.
• Benign prostatic hyperplasia (BPH). Oral milk thistle has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: Preliminary clinical research shows that taking a milk thistle extract of silymarin 190 mg along with selenium 80 mcg orally three times daily for 6 months may improve lower urinary tract symptoms, urinary flow rates, and residual volumes in adults aged 45-70 years with BPH when compared with placebo (88155). It is unclear if these effects are due to milk thistle, selenium, or the combination.
• Beta-thalassemia. Meta-analyses of clinical studies in patients with beta-thalassemia suggest that oral silymarin, a constituent of milk thistle, reduces serum ferritin levels. Details: Most small clinical studies and meta-analyses of these studies show that taking silymarin in conjunction with conventional iron chelation medications such as deferiprone, deferasirox, or deferoxamine, is more effective for reducing serum ferritin levels than taking a conventional medication alone (88154,98452,107375). In one meta-analysis, the combination of silymarin and deferasirox appeared to be more effective than combinations with other iron chelation medications (107375). However, one preliminary clinical study in patients 12 years of age and older with beta-thalassemia shows that taking a milk thistle extract containing 70% to 80% silymarin (Legalon, Madaus GmbH) 140 mg orally three times daily for 3 months, in conjunction with deferoxamine, does not improve serum ferritin when compared with deferoxamine alone (63212). This difference in outcome is likely due to the shorter duration of therapy. Silymarin also does not seem to affect total iron binding capacity or liver iron concentration in patients with beta-thalassemia (107375).
• Chemotherapy-induced acral erythema. It is unclear if topical milk thistle is beneficial in patients with acral erythema due to capecitabine. Details: Preliminary clinical research shows that applying a gel containing a milk thistle extract of silymarin 1% twice daily to the hands and feet, starting from the first day of chemotherapy and continuing for 9 weeks thereafter, prolongs the time to onset of acral erythema and decreases its severity when compared with placebo in patients with gastrointestinal cancer who are receiving capecitabine for the first time (95022).
• Chemotherapy-induced hepatotoxicity. Results of clinical studies are mixed over whether oral milk thistle prevents or improves chemotherapy-induced hepatotoxicity. Details: One small clinical study in children and adults up to age 21 with acute lymphoblastic leukemia (ALL) and elevated liver function tests (LFTs) shows that taking a specific product containing the milk thistle constituent silibinin (Siliphos, Thorne Research, Inc.) 80-320 mg (depending on patient weight) daily for 28 days concurrently with chemotherapy does not improve LFTs or bilirubin levels when compared with placebo (63218). Another small clinical study in patients with non-metastatic breast cancer receiving doxorubicin, cyclophosphamide, and paclitaxel shows that taking a specific milk thistle extract of silymarin (Livergol, Goldaru Pharmaceutical Company) 140 mg three times daily with meals for 4 weeks does not improve fatty liver grading or LFTs when compared with placebo (105795). Conversely, a large clinical study in children aged 5-14 with elevated liver enzymes and receiving chemotherapy for ALL shows that taking silymarin 70 mg capsules twice daily or 50 mg syrup three times daily for 9 months modestly improves aspartate aminotransferase (AST), alanine aminotransferase (ALT), and bilirubin levels, but does not improve alkaline phosphatase or albumin levels (113144). Similarly, observational research in patients with a variety of solid tumors and elevated LFTs due to chemotherapy or targeted therapy suggests that taking silymarin 150-900 mg daily is associated with reduced or stabilized LFTs in over half of patients; however, doses above 300-450 mg daily don't seem to have much more benefit (111176). The interpretation of these results is limited by the lack of a comparator group.
• Chemotherapy-induced nephrotoxicity. It is unclear if oral milk thistle is beneficial for the prevention of cisplatin-induced nephrotoxicity. Details: A small clinical study shows that taking a milk thistle extract standardized to 70% to 80% silymarin (Liverherb, Amin Pharmaceutical Company) 140 mg orally three times daily with meals, starting 24-48 hours before cisplatin and continuing until the end of three 21-day cycles, does not prevent cisplatin-induced nephrotoxicity when compared with placebo (95025).
• Chemotherapy-induced peripheral neuropathy. It is unclear if oral milk thistle is beneficial for chemotherapy-induced peripheral neuropathy. Details: A small clinical study in adults with cancer receiving cisplatin chemotherapy shows that taking a specific product (Livergol, Goldaru) containing milk thistle 140 mg three times daily for 3 months improves overall symptoms of chemotherapy-induced peripheral neuropathy when compared to baseline, but not when compared with placebo, with the possible exception of hyposthesia to touch and pins and needles sensation which had worsened only in the placebo group (113979).
• Cirrhosis. It is unclear if oral milk thistle extracts of silymarin are beneficial for cirrhosis from various causes. Details: Preliminary clinical research shows that taking a milk thistle extract of silymarin 420 mg orally daily for up to 4 years might improve liver function tests and decrease mortality in people with cirrhosis due to a variety of causes (2616,63145,63278,63340). However, a meta-analysis of clinical research evaluating milk thistle studies for the treatment of various liver diseases shows that effect sizes are generally small or lack statistical significance (63161). An observational study in adults with hepatitis B virus-related liver cirrhosis suggests that taking milk thistle 150 mg 2-3 times daily for at least 30 days in combination with anti-viral therapy is associated with lower mortality and liver transplantation rates at 1- and 2-year follow up and greater improvement in international normalized ratio, model for end-stage liver disease score, and the Charlson comorbidity index at 1-year follow-up when compared with anti-viral therapy alone (113986).
• Contrast induced nephropathy. It is unclear if oral milk thistle is beneficial for reducing the risk of nephropathy from contrast agents. Details: Population research in Taiwanese patients with liver cirrhosis has found that taking silymarin daily for at least 90 days during a one-year period does not reduce the risk of contrast-induced nephropathy during the following four or more years (98453).
• Coronavirus disease 2019 (COVID-19). It is unclear if oral milk thistle is beneficial for COVID-19. Details: Preliminary clinical research in adults hospitalized with COVID-19 requiring non-invasive oxygen support shows that taking a specific milk thistle product (SinaLive, Exir Nano Sina Company), 70 mg orally three times daily for 2 weeks, does not improve time to symptom resolution, lung scores, or length of stay when compared with placebo (109504).
• Critical illness (trauma). It is unclear if oral milk thistle is beneficial in critically ill patients with trauma-induced liver injury. Details: One small clinical study in patients admitted to the intensive care unit (ICU) due to trauma-induced liver injury shows that taking a specific milk thistle extract (Livergol, Goldaru Pharmaceutical Company) containing silymarin 140 mg three times daily for 14 days reduces markers of liver injury, including alanine aminotransferase (ALT) and aspartate aminotransferase (AST), when compared with placebo (105793). Whether this milk thistle extract improves morbidity, mortality, or length of ICU stay in these patients is unclear.
• Diabetic nephropathy. It is unclear if oral milk thistle is beneficial for improving kidney function in patients with this condition. Details: Preliminary clinical research in type 2 diabetic patients with diabetic nephropathy shows that taking a milk thistle extract of silymarin 140 mg orally three times daily for 3 months, in combination with conventional treatment decreases the urine albumin to creatinine ratio when compared with placebo. However, serum creatinine and estimated glomerular filtration rate are not improved (63250).
• Dyspepsia. Oral milk thistle has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: A specific combination product containing milk thistle (Iberogast, Medical Futures, Inc.) seems to improve symptoms of dyspepsia. The combination includes milk thistle plus peppermint leaf, German chamomile, caraway, licorice, clown's mustard plant, celandine, angelica, and lemon balm (19532). A meta-analysis of clinical research using this combination product shows that taking 1 mL orally three times daily over a period of 4 weeks reduces severity of acid reflux, epigastric pain, cramping, nausea, and vomiting when compared with placebo (13089).
• Endometriosis. It is unclear if oral milk thistle is beneficial in patients with endometriosis. Details: Preliminary clinical research in females with ovarian endometrioma shows that taking a specific silymarin product (Goldaru Pharma) 140 mg twice daily for 12 weeks moderately improves pain scores, but not other sexual function scores, when compared with placebo (110486). However, some researchers have also recommended to avoid using milk thistle in estrogen-sensitive conditions, such as endometriosis, due to its estrogenic effects (93025,93026).
• Gambling disorder. It is unclear if oral milk thistle is beneficial for gambling disorder. Details: A small clinical study in adults with gambling disorder shows that taking milk thistle 150 mg twice daily for 2 weeks and then 300 mg daily for the next 6 weeks does not improve symptoms associated with gambling disorder, including gambling urges, thoughts, and behaviors, or improve symptoms of anxiety and depression when compared with placebo (113974). The interpretation of these results is limited by the small sample size and a strong placebo effect.
• Hepatitis. Small clinical studies suggest that oral milk thistle extracts of silymarin may improve hepatitis symptoms. It is unclear whether these products can improve liver function in these patients. Details: In people with hepatitis due to a variety of causes, taking a milk thistle extract containing 70% to 80% silymarin (Legalon, Madaus GmbH) 140 mg orally three times daily for 4 weeks reduces symptoms such as jaundice, dark urine, and scleral icterus, but does not improve liver function tests (LFTs) (63210,63317). However, some improvements in LFTs are seen with a silybin-phosphatidylcholine complex (Silipide, Inverni della Beffa Research and Development Laboratories) taken as 160-360 mg orally daily for 2 weeks to 3 months (63320,63321). However, there are methodological problems with these latter studies.
• Hepatitis B. Small clinical studies suggest that oral milk thistle extracts may improve liver function in people with hepatitis B, although it is unclear if these products can improve disease-related complications. Details: Preliminary clinical studies suggest that taking a milk thistle extract containing 70% to 80% silymarin (Legalon, Madaus GmbH) 140 mg orally three times daily for 28 days to one year, or a silybin-phosphatidylcholine complex (Silipide, Inverni della Beffa Research and Development Laboratories) 240 mg orally twice daily for 7 days, improves liver function tests (LFTs) and liver histology (7356,63263,63299). However, another study shows that taking a milk thistle extract of silymarin 140 mg orally three times daily for 5-25 days has no effect of LFTs (63288). A meta-analysis of clinical research and a review conclude that any clinical effect of milk thistle in people with viral hepatitis is very limited and results suggest that it lacks a significant effect on mortality, liver disease complications, or liver histology (17228,63192).
• Hepatitis C. Small clinical studies suggest that oral milk thistle extracts may improve liver function but do not seem to reduce hepatitis C virus (HCV) RNA levels. Details: Preliminary clinical studies show that taking a milk thistle extract containing 70% to 80% silymarin (Legalon, Madaus GmbH) 140 mg orally three times daily for 3-12 months, or a silybin-phosphatidylcholine complex (Silipide, Inverni della Beffa Research and Development Laboratories) 240 mg orally twice daily for 7 days, improves liver function tests (LFTs) and liver histology (7356,63299). However, other studies report that taking silymarin 125-140 mg three times daily for up to one year, 166 mg twice daily for 3 months, or 400 mg daily for 8 weeks does not improve serum HCV RNA levels, anti-HCV antibody levels, LFTs, or hepatomegaly (13170,63208,63247,63288,108658). Also, taking higher doses of silymarin, up to 700 mg three times daily for 6 months, does not have a significant effect on serum HCV RNA levels or LFTs when compared with placebo (63251). A meta-analysis of clinical research and a review conclude that any clinical effect of milk thistle in people with viral hepatitis is limited and most results show that milk thistle lacks a significant effect on mortality, liver disease complications, or liver histology (17228,63192,88156). Preliminary clinical research in adults with HCV-related advanced chronic liver disease shows that taking a specific milk thistle combination product containing silybinphospholipid complex 303 mg, vitamin D 10 mcg, and vitamin E 15 mg (Realsil 100 D, Ibi Lorenzini), twice daily for 12 months, improves liver stiffness scores, but not liver fibrosis scores, when compared with control (108659). It is unclear if this effect is due to milk thistle, other ingredients, or the combination.
• Hypercholesterolemia. Oral milk thistle has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: A meta-analysis of three clinical trials in adults with hypercholesterolemia shows that taking a specific combination product (Berberol, PharmExtracta) containing milk thistle extract 105 mg and tree turmeric extract 588 mg twice daily for 3 months, along with diet and exercise, reduces levels of low-density lipoprotein (LDL) cholesterol by an average of 34 mg/dL when compared with diet and exercise alone. There was no effect on high-density lipoprotein (HDL) cholesterol or triglyceride levels (101158). The studies included in this meta-analysis are generally of low quality, lasted for no more than 12 months, and sometimes include patients with statin intolerance (95019,96140,101158). It is unclear if the effects of this product are due to milk thistle extract, tree turmeric extract, or the combination. Other clinical research shows that taking a similar product (Berberol K, PharmExtracta) containing milk thistle extract 105 mg, tree turmeric extract of berberine 500 mg, and monacolin K and KA 10 mg, taken once daily for 3 months along with diet and exercise, reduces levels of LDL cholesterol by about 28% when compared with diet and exercise alone in patients with hypercholesterolemia (97625). It is possible that any benefit of this product is due to the monacolin content.
• Hyperlipoproteinemia. It is unclear if oral milk thistle is beneficial in patients with hyperlipoproteinemia secondary to liver disease. Details: One very small crossover study shows that taking a milk thistle extract containing 70% to 80% silymarin (Legalon, Madaus GmbH) 420 mg orally daily for 7 months does not significantly improve cholesterol levels in patients with hyperlipoproteinemia secondary to liver disease when compared with placebo (63255).
• Hypoxic liver injury. It is unclear if oral milk thistle is beneficial for reducing liver injury in patients with hypoxia. Details: Preliminary clinical research in patients presenting to the emergency department with hypoxia shows that taking a milk thistle extract of silymarin 280 mg every 8 hours for 3 days reduces markers of liver injury, including alanine aminotransferase (ALT), aspartate aminotransferase (AST), and gamma-glutamyl transferase (GGT), when compared with placebo (103871).
• Infertility. It is unclear if oral milk thistle is beneficial for patients undergoing in vitro fertilization. Details: Preliminary clinical research shows that taking a milk thistle extract of silymarin 70 mg orally three times daily in combination with human chorionic gonadotropin (HCG) lowers the proportion of early and total apoptosis of follicle cells during in vitro fertilization due to male infertility. However, it does not have an effect on the number of oocytes retrieved or the thickness of the endometrium when compared with HCG plus placebo (63227).
• Lactation. It is unclear if oral milk thistle is beneficial for increasing milk production. Details: A small clinical study shows that taking a milk thistle extract standardized to 60% silymarin (BIO-C, Milte Italia S.r.l.) 240 mg twice daily for 4 weeks does not increase milk production when compared with placebo in mothers of preterm newborns (95027).
• Melasma. It is unclear if topical milk thistle is beneficial in patients with melasma. Details: Preliminary clinical research in adults with melasma shows that applying silymarin 1.4% cream twice daily for 3 months moderately improves melasma appearance scores when compared to baseline. These improvements were similar to hydroquinone cream 2% (110489). One small clinical trial in females with melasma shows that application of silymarin 1.4% cream twice daily to the affected area for 3 months is as effective for improving melasma area and severity as a specific type of laser therapy (low fluence Q switched ND:YAG 1064 nm) (105791).
• Menopausal symptoms. It is unclear if oral milk thistle reduces menopausal symptoms such as hot flashes. Details: One small clinical study in postmenopausal patients shows that taking milk thistle fruit extract 200 mg, containing 80% silymarin, twice daily for 8 weeks seems to reduce the number and severity of daily hot flashes and overall climacteric symptoms when compared with taking placebo (105053). This finding is limited by incomplete reporting and potentially inadequate blinding. Other preliminary clinical research has evaluated milk thistle in combination with black cohosh, dong quai, red clover, American ginseng, and chasteberry (Phyto-Female, SupHerb), with some evidence of benefit for reducing hot flashes and night sweats. (19552).
• Metabolic dysfunction-associated steatotic liver disease (MASLD). It is unclear if oral milk thistle is beneficial for MASLD. Details: A moderate-sized, open-label, non-controlled study in patients with MASLD shows that taking milk thistle standardized to silymarin 150 mg twice daily for 6 months does not improve liver stiffness or liver enzymes when compared with essential phospholipids. It is unclear if any changes in these outcomes are statistically significant when compared to baseline (114462). The validity of these findings is limited by the lack of a placebo group, lack of reporting of changes to diet and exercise, unclear statistical analysis and reporting, and the use of a per protocol analysis instead of intention-to-treat analysis. Also review milk thistle's effectiveness in nonalcoholic fatty liver disease (NAFLD), a similar condition.
• Metabolic syndrome. Oral silymarin, a constituent of milk thistle, seems to improve some of the laboratory abnormalities associated with metabolic syndrome. Details: A meta-analysis of 11 low-quality clinical trials in adults with metabolic syndrome, conducted in Asia and Africa, shows that silymarin, 140-2100 mg daily for 45 days to 12 months, modestly reduces fasting blood glucose, glycated hemoglobin, total cholesterol, triglyceride, and low-density lipoprotein cholesterol levels, and increases high-density lipoprotein cholesterol levels, when compared with placebo (107374).
• Multiple sclerosis (MS). Oral milk thistle has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: Preliminary clinical research in patients with MS shows that taking a supplement containing a milk thistle extract of silymarin 150 mg in combination with ferulic acid, gamma-oryzanol, and apigenin twice daily for 3-24 months may stabilize clinical symptoms of MS when compared to baseline (63223). It is unclear if this effect is due to milk thistle, other ingredients, or the combination.
• Nonalcoholic fatty liver disease (NAFLD). Small clinical studies suggest that oral milk thistle extracts of silymarin may slightly improve markers of liver function patients with NAFLD. Details: Four meta-analyses of up to 23 mostly small clinical trials in patients with NAFLD show that taking milk thistle products containing a total of silymarin 140-2100 mg daily, either alone or in combination with other ingredients, for 8-48 weeks reduces aspartate aminotransferase (AST) by 7-13 IU/L and alanine aminotransferase (ALT) by 9-17 IU/L when compared with control (97622,105051,113976,113982). However, these changes in liver enzymes may not be clinically impactful and some experts note that serum AST levels do not reliably reflect the spectrum of liver histology in patients with NAFLD (98130). Metabolic indices have also been evaluated. A meta-analysis of up to 20 mostly small clinical studies in patients with NAFLD shows that taking milk thistle for up to 48 weeks slightly improves serum lipids when compared with control (113976). A small clinical study in adults with NAFLD and a body-mass index (BMI) of at least 35 kg/m² shows that taking milk thistle extract 140 mg 4 times daily for 8 weeks, in addition to lifestyle modifications, reduces BMI by approximately 1 kg/m² when compared with placebo with lifestyle modifications (108657). However, another small clinical trial in adults with NAFLD and a BMI of at least 40 kg/m² shows that taking a specific silymarin product (Livergol, Goldaru Pharmaceuticals) 140 mg three times daily for 4 weeks did not reduce BMI or improve liver enzymes, such as AST and ALT, when compared with placebo (110484). A meta-analysis of 7 small clinical trials also shows there is little to no change in BMI associated with silymarin use in these patients (113976). One small clinical study in patients with NAFLD shows that taking a specific combination product (Eurosil 85, MEDAS SL) containing milk thistle extract standardized to silymarin 540 mg and vitamin E 36 mg daily for 3 months, in addition to following a low-calorie diet, does not appear to improve NAFLD-Fibrosis score or fatty liver index (FLI) when compared with following a low-calorie diet alone (96261), though a meta-analysis of 2 small clinical studies in patients with NAFLD shows that taking milk thistle for 12-24 weeks does reduce FLI when compared with control (113976). Also review milk thistle's effectiveness in metabolic dysfunction-associated steatotic liver disease (MASLD), a similar condition.
• Nonalcoholic steatohepatitis (NASH). It is unclear if oral milk thistle is beneficial in patients with NASH. Details: Clinical research in patients with NASH shows that taking a milk thistle extract of silymarin 700 mg three times daily for 48 weeks improves fibrosis in more patients when compared with placebo (96107). However, there is no significant between-group difference in global histological improvement with this product (96107) or with a specific silymarin product (Legalon, Rottapharm Madaus, Mylan) 420 or 700 mg three times daily for 48-50 weeks (101150). Pooling 1 of these clinical studies (96107) into a meta-analysis with another clinical trial that evaluated milk thistle in combination with phosphatidylcholine and vitamin E suggests an improvement in fibrosis by at least one stage when compared with placebo (113984). However, it is unclear if this effect is due to milk thistle, other ingredients, or the combination. Metabolic indices have also been evaluated. A meta-analysis of small clinical studies in patients with NASH or nonalcoholic fatty liver disease (NAFLD) shows that taking milk thistle reduces aspartate aminotransferase (AST) by about 13 IU/L, alanine aminotransferase (ALT) by about 17 IU/L, serum triglycerides by about 23 mg/dL and increases high-density lipoprotein cholesterol by about 2 mg/dL, but does not alter gamma-glutamyl transferase, total cholesterol, low-density lipoprotein cholesterol, body mass index, or insulin resistance when compared with control (113982). However, trials on NAFLD and NASH were not analyzed separately which limits the generalizability of these findings to patients with NASH specifically. The dose and duration of milk thistle treatment was also not described.
• Obesity. It is unclear if oral milk thistle is beneficial in patients with obesity. Details: A meta-analysis of 11 clinical studies in healthy adults and adults with various medical conditions shows that taking milk thistle does not reduce body weight or body mass index when compared with placebo or control (113987). A very small open-label study in adult females with obesity suggests that taking a specific milk thistle extract product (Neocholal-S, Italmex) 151.5 mg, containing silybin 45 mg, twice daily for 12 weeks does not reduce body weight but may reduce fasting blood glucose levels and insulin resistance when compared to baseline (113980). The validity of this study is limited by the lack of a comparator group and very small sample size.
• Obsessive-compulsive disorder (OCD). It is unclear if oral milk thistle is beneficial in patients with OCD. Details: Preliminary clinical research shows that taking milk thistle leaf extract 200 mg orally three times daily for 8 weeks has a limited effect on OCD symptom scores when compared to baseline, but does not provide any benefit over fluoxetine 10 mg three times daily (63219).
• Parkinson disease. Oral milk thistle has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: Preliminary clinical research shows that taking a supplement containing a milk thistle extract of silymarin 150 mg in combination with ferulic acid, gamma-oryzanol, and apigenin orally twice daily for 3 months to 24 months may stabilize clinical symptoms in patients with Parkinson disease when compared to baseline (63223). It is unclear if this effect is due to milk thistle, other ingredients, or the combination.
• Postpartum complications. It is unclear if topical milk thistle is beneficial in postpartum patients with an episiotomy. Details: Preliminary clinical research in postpartum patients shows that applying milk thistle 3% in Eucerin ointment twice daily to the suture site for 10 days reduces episiotomy pain and improves the healing rate when compared with placebo. The milk thistle product was prepared with an ethanolic extract of the seeds to provide 1.53% silybin (107373).
• Prostate cancer. Oral milk thistle has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: Preliminary clinical research in patients with a history of prostate cancer who have had radiotherapy or radical prostatectomy shows that taking a dietary supplement containing a milk thistle extract of silymarin 160 mg, soy isoflavones (Novasoy, ADM) 62.5 mg, lycopene (Lyc-O-Mato, LycoRed Natural Products Industries, Ltd.) 15 mg, vitamins, minerals, and antioxidants orally daily for 10 weeks increases the time it takes for prostate-specific antigen (PSA) levels to double by 2.6-fold when compared with placebo (60361).
• Radiation dermatitis. It is unclear if topical milk thistle is beneficial in patients with dermatitis due to radiation. Details: Preliminary clinical research in females with breast cancer undergoing radiotherapy shows that applying a specific topical product containing a milk thistle extract of silymarin (Leviaderm, Madaus GmbH) significantly reduces the incidence of radiation dermatitis and prolongs the time to the onset of radiation dermatitis when compared with applying a panthenol-containing cream (63239). Additionally, meta-analysis pooling this study (63239) with one other small clinical study also shows that applying a cream or gel containing milk thistle extract reduces the incidence radiation dermatitis when compared with control (113674).
• Radiation mucositis. It is unclear if oral milk thistle is beneficial for preventing or treating mucositis due to radiation. Details: One small clinical study in patients with head and neck cancer receiving radiotherapy for the first time shows that taking a specific product containing a milk thistle extract of silymarin (Livergol, Goldaru Pharmaceutical Company), 140 mg three times daily starting from the first day of radiotherapy and continuing for 6 weeks thereafter, reduces the severity and prolongs the time to onset of radiation-induced mucositis when compared with placebo (95021).
• Toxin-induced liver damage. Most small clinical studies suggest that oral milk thistle extracts or constituents may reduce liver injury in people exposed to some, but not all, toxins and medications known to cause liver damage. Details: Taking a milk thistle extract containing 70% to 80% silymarin (Legalon, Madaus GmbH) 420 mg orally daily for up to one month improves liver function tests (LFTs) in people with abnormal LFTs due to chronic occupational exposure to paints or organic solvents such as toluene or xylene (2614,63280). Milk thistle extract has also shown some benefit for reducing drug-induced liver injury (DILI). In patients on isotretinoin therapy for acne, taking a specific milk thistle extract containing silymarin (Livergol, Goldaru Pharmaceutical Company) 140 mg daily for 30 days improves LFTs when compared with placebo (102852). A small clinical study in patients with relapsing-remitting multiple sclerosis who were initiating therapy with fingolimod shows that taking a specific milk thistle extract (Livergol, Goldaru Pharmaceutical Company) containing silymarin 140 mg daily for 6 months prevents fingolimod-induced LFT elevations when compared with placebo (105794). In patients receiving treatment for tuberculosis with rifampin, isoniazid, pyrazinamide, ethambutol, and streptomycin, taking the milk thistle constituent silibinin 70 mg orally three times daily for 6-12 months reduces the rate of liver toxicity to 14% compared with 53% in patients taking glucuronolactone 200 mg orally three times daily (63224). Additionally, in patients receiving standard treatment for tuberculosis with isoniazid, rifampicin, pyrazinamide, and ethambutol, taking a milk thistle extract of silymarin 140 mg orally three times daily for 4 weeks decreases the risk of DILI by 28% when compared with placebo. About 1 in every 4 patients who take silymarin for 4 weeks would avoid DILI (95024). A small clinical study in Iran, also in adults receiving standard treatment for tuberculosis, shows that taking a milk thistle extract of silymarin 150 mg twice daily for 2 weeks modestly improves LFTs when compared with control. None of the 16 patients in the silymarin group developed DILI compared with 2 of 21 patients in the control group; however, this finding was not statistically significant (112230). The interpretation of these findings is limited by the short study duration. However, taking a milk thistle extract of silymarin 420 mg orally daily for 3 months does not seem to prevent liver toxicity associated with tacrine (Cognex) therapy in people with Alzheimer disease (63140). Other research in people with elevated LFTs due to long-term therapy with phenothiazine or butyrophenone antipsychotic medications shows that taking silymarin 800 mg orally daily for 3 months also does not improve LFTs when compared with placebo (63344). A retrospective study in patients with DILI of various offending agents has also found that taking a milk thistle extract, containing a median of 450 mg silybin daily for 24 days is associated with 1.7-2.8 times higher likelihood of LFT normalization when compared with control (110485).
• Trichotillomania. It is unclear if oral milk thistle is beneficial in patients with this condition. Details: Preliminary clinical research in patients 12-65 years of age shows that taking milk thistle 150 mg twice daily for 2 weeks, and then 300 mg twice daily for 4 weeks, does not improve symptoms of trichotillomania when compared with placebo (99426).
• Ulcerative colitis. It is unclear if oral milk thistle is beneficial in patients with this condition. Details: Preliminary clinical research in patients 16-75 years of age shows that taking a specific milk thistle extract of silymarin (Livergol, Goldaru Pharmaceutical Company) 140 mg daily for 6 months, in conjunction with standard medications, decreases disease activity and helps maintain remission when compared with placebo in patients with ulcerative colitis (95029).
• Vitiligo. It is unclear if oral milk thistle reduces the severity of this condition. Details: Preliminary clinical research in a small number of patients with vitiligo shows that taking a specific milk thistle extract containing silymarin (Livergol, Goldaru Pharmaceutical Company) 140 mg twice daily along with phototherapy for 3 months does not improve the severity of vitiligo when compared with phototherapy plus placebo (102851). More evidence is needed to rate milk thistle for these uses.

(Read more about MILK THISTLE)

LIKELY SAFE ...when used orally in amounts commonly found in foods. Artichoke has Generally Recognized As Safe status (GRAS) for use in foods in the US (4912).

POSSIBLY SAFE ...when used orally and appropriately in medicinal amounts. Artichoke extract has been used with apparent safety at doses up to 3200 mg daily for up to 12 weeks (6282,15204,52235,91475,91478,100934). Artichoke leaf powder has been used with apparent safety at a dose of 1000 mg daily for up to 8 weeks (104133). Cynarin, a constituent in artichoke extract, has been used with apparent safety at daily doses of 750 mg daily for up to 3 months or 60 mg daily for up to 7 months (1423,1424,52222,52223,52236).

PREGNANCY AND LACTATION:
There is insufficient reliable information available about the safety of artichoke when used in medicinal amounts during pregnancy or lactation; avoid amounts greater than those found in foods.

(Read more about ARTICHOKE)

LIKELY SAFE ...when used orally in amounts commonly found in foods. Dandelion has Generally Recognized As Safe (GRAS) status in the US (4912).

POSSIBLY SAFE ...when used orally and appropriately in medicinal amounts (12). There is insufficient reliable information available about the safety of dandelion when used topically.

PREGNANCY AND LACTATION:
Insufficient reliable information available; avoid using amounts greater than those in foods.

(Read more about DANDELION)

LIKELY SAFE ...when used orally in amounts commonly found in foods. Licorice has Generally Recognized as Safe (GRAS) status in the US (4912).

POSSIBLY SAFE ...when licorice products that do not contain glycyrrhizin (deglycyrrhizinated licorice) are used orally and appropriately for medicinal purposes. Licorice flavonoid oil 300 mg daily for 16 weeks, and deglycyrrhizinated licorice products in doses of up to 4.5 grams daily for up to 16 weeks, have been used with apparent safety (6196,11312,11313,17727,100984,102960). ...when licorice products containing glycyrrhizin are used orally in low doses, short-term. Licorice extract 272 mg, containing glycyrrhizin 24.3 mg, has been used daily with apparent safety for 6 months (102961). A licorice extract 1000 mg, containing monoammonium glycyrrhizinate 240 mg, has been used daily with apparent safety for 12 weeks (110320). In addition, a syrup providing licorice extract 750 mg has been used twice daily with apparent safety for 5 days (104558). ...when applied topically. A gel containing 2% licorice root extract has been applied to the skin with apparent safety for up to 2 weeks. (59732). A mouth rinse containing 5% licorice extract has been used with apparent safety four times daily for up to one week (104564).

POSSIBLY UNSAFE ...when licorice products containing glycyrrhizin are used orally in large amounts for several weeks, or in smaller amounts for longer periods of time. The European Scientific Committee on Food recommends that a safe average daily intake of glycyrrhizin should not exceed 10 mg (108577). In otherwise healthy people, consuming glycyrrhizin daily for several weeks or longer can cause severe adverse effects including pseudohyperaldosteronism, hypertensive crisis, hypokalemia, cardiac arrhythmias, and cardiac arrest. Doses of 20 grams or more of licorice products, containing at least 400 mg glycyrrhizin, are more likely to cause these effects; however, smaller amounts have also caused hypokalemia and associated symptoms when taken for months to years (781,3252,15590,15592,15594,15596,15597,15599,15600,16058)(59731,59740,59752,59785,59786,59787,59792,59795,59805,59811)(59816,59818,59820,59822,59826,59828,59849,59850,59851,59867)(59882,59885,59888,59889,59895,59900,59906,97213,110305). In patients with hypertension, cardiovascular or kidney conditions, or a high salt intake, as little as 5 grams of licorice product or 100 mg glycyrrhizin daily can cause severe adverse effects (15589,15593,15598,15600,59726).

PREGNANCY: UNSAFE
when used orally. Licorice has abortifacient, estrogenic, and steroid effects. It can also cause uterine stimulation. Heavy consumption of licorice, equivalent to 500 mg of glycyrrhizin per week (about 250 grams of licorice per week), during pregnancy seems to increase the risk of delivery before gestational age of 38 weeks (7619,10618). Furthermore, high intake of glycyrrhizin, at least 500 mg per week, during pregnancy is associated with increased salivary cortisol levels in the child by the age of 8 years. This suggests that high intake of licorice during pregnancy may increase hypothalamic-pituitary-adrenocortical axis activity in the child (26434); avoid using.

LACTATION:
Insufficient reliable information available; avoid using.

(Read more about LICORICE)

LIKELY SAFE ...when used orally and appropriately. A specific milk thistle extract standardized to contain 70% to 80% silymarin (Legalon, Madaus GmbH) has been safely used in doses up to 420 mg daily for up to 4 years (2613,2614,2616,7355,63210,63212,63278,63280,63299,63340)(88154,97626,105792). Higher doses of up to 2100 mg daily have been safely used for up to 48 weeks (63251,96107,101150). Another specific milk thistle extract of silymarin (Livergol, Goldaru Pharmaceutical Company) has been safely used at doses of 140 mg daily for up to 6 months and doses of 420 mg daily for up to 6 weeks (95021,95029,102851,102852,105793,105794,105795,113979). Some isolated milk thistle constituents also appear to be safe. Silibinin (Siliphos, Thorne Research) has been used safely in doses up to 320 mg daily for 28 days (63218). Some combination products containing milk thistle and other ingredients also appear to be safe. A silybin-phosphatidylcholine complex (Silipide, Inverni della Beffa Research and Development Laboratories) has been safely used in doses of 480 mg daily for 7 days (7356) and 240 mg daily for 3 months (63320). Tree turmeric and milk thistle capsules (Berberol, PharmExtracta) standardized to contain 60% to 80% silybin have been safely used twice daily for up to 12 months (95019,96140,96141,96142,97624,101158).

POSSIBLY SAFE ...when used topically and appropriately, short-term. A milk thistle extract cream standardized to silymarin 0.25% (Leviaderm, Madaus GmbH) has been used safely throughout a course of radiotherapy (63239). Another milk thistle extract cream containing silymarin 1.4% has been used with apparent safety twice daily for 3 months (105791,110489). A cream containing milk thistle fruit extract 25% has been used with apparent safety twice daily for up to 12 weeks (111175). A milk thistle extract gel containing silymarin 1% has been used with apparent safety twice daily for 9 weeks (95022). There is insufficient reliable information available about the safety of intravenous formulations of milk thistle or its constituents.

PREGNANCY AND LACTATION:
While research in an animal model shows that taking milk thistle during pregnancy and lactation does not adversely impact infant development (102850), there is insufficient reliable information available about its safety during pregnancy or lactation in humans; avoid using.

CHILDREN: POSSIBLY SAFE
when used orally and appropriately, short-term. A milk thistle extract 140 mg three times daily has been used with apparent safety for up to 9 months (88154,98452). A specific product containing the milk thistle constituent silybin (Siliphos, Thorne Research Inc.) has been used with apparent safety in doses up to 320 mg daily for up to 4 weeks in children one year of age and older (63218).

(Read more about MILK THISTLE)

ANTIDIABETES DRUGS Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, artichoke leaf extract may increase the risk of hypoglycemia when taken with antidiabetes drugs.  Details A meta-analysis of small clinical studies shows that taking artichoke leaf extract for 8-12 weeks can modestly reduce fasting plasma glucose when compared with placebo (105768).

ANTIHYPERTENSIVE DRUGS Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, artichoke leaf extract may increase the risk of hypotension when taken with antihypertensive drugs.  Details A meta-analysis of small clinical studies in patients with hypertension shows that taking artichoke can reduce systolic blood pressure by around 3 mmHg and diastolic blood pressure by around 2 mmHg when compared with placebo (105767).

CYTOCHROME P450 2B6 (CYP2B6) SUBSTRATES Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, artichoke might increase serum levels of drugs metabolized by CYP2B6.  Details In vitro research shows that artichoke leaf extract inhibits CYP2B6 activity (97717). However, this interaction has not been reported in humans.

CYTOCHROME P450 2C19 (CYP2C19) SUBSTRATES Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, artichoke might increase serum levels of drugs metabolized by CYP2C19.  Details In vitro research shows that artichoke leaf extract inhibits CYP2C19 activity (97717). However, this interaction has not been reported in humans.

(Read more about ARTICHOKE)

ANTICOAGULANT/ANTIPLATELET DRUGS Interaction Rating = Moderate Be cautious with this combination. Severity = High •  Occurrence = Possible •  Level of Evidence = D Theoretically, taking dandelion root along with anticoagulant or antiplatelet drugs might increase the risk of bruising and bleeding.  Details In vitro research suggests that dandelion root inhibits platelet aggregation (18291).

ANTIDIABETES DRUGS Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, dandelion might increase the risk for hypoglycemia when used with antidiabetes drugs.  Details Laboratory research suggests that dandelion extract may have moderate alpha-glucosidase inhibitor activity and might also increase insulin secretion (13474,90926). Also, in a case report, a 58-year-old woman with type 2 diabetes who was being treated with insulin developed hypoglycemia 2 weeks after beginning to eat salads containing dandelion (46960).

CYTOCHROME P450 1A2 (CYP1A2) SUBSTRATES Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, dandelion might increase levels of drugs metabolized by CYP1A2.  Details Laboratory research suggests that dandelion might inhibit CYP1A2 (12734). So far, this interaction has not been reported in humans. However, until more is known, watch for an increase in the levels of drugs metabolized by CYP1A2 in patients taking dandelion.

GLUCURONIDATED DRUGS Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, dandelion might increase the clearance of drugs that are UDP-glucuronosyltransferase substrates.  Details There is some preliminary evidence that dandelion might induce UDP-glucuronosyltransferase, a phase II enzyme (12734).

LITHIUM Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Probable •  Level of Evidence = D Theoretically, through diuretic effects, dandelion might reduce excretion and increase levels of lithium.  Details Animal research suggests that dandelion has diuretic properties (13475). As diuretics can increase serum lithium levels, the dose of lithium might need to be decreased when taken with dandelion.

POTASSIUM-SPARING DIURETICS Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, dandelion might increase the risk of hyperkalemia when taken with potassium-sparing diuretics.  Details Dandelion contains significant amounts of potassium (13465).

QUINOLONE ANTIBIOTICS Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, dandelion might lower fluoroquinolone levels.  Details Animal research shows that dandelion reduces absorption of ciprofloxacin and can lower levels by 73% (13477). However, this effect has not been reported in humans.

(Read more about DANDELION)

ANTIHYPERTENSIVE DRUGS Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = B Theoretically, licorice might reduce the effects of antihypertensive drugs.  Details In human research, licorice increases blood pressure in a dose-dependent manner (1372,7620,59877).

CISPLATIN (Platinol-AQ) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, licorice might reduce the effects of cisplatin.  Details In animal research, licorice diminished the therapeutic efficacy of cisplatin (59763).

CORTICOSTEROIDS Interaction Rating = Moderate Be cautious with this combination. Severity = High •  Occurrence = Possible •  Level of Evidence = D Theoretically, concomitant use of licorice and corticosteroids might increase the side effects of corticosteroids.  Details Case reports suggest that concomitant use of licorice and oral corticosteroids, such as hydrocortisone, can potentiate the duration of activity and increase blood levels of corticosteroids (3252,12672,20040,20042,48429,59756). Additionally, in one case report, a patient with neurogenic orthostatic hypertension stabilized on fludrocortisone 0.1 mg twice daily developed pseudohyperaldosteronism after recent consumption of large amounts of black licorice (108568).

CYTOCHROME P450 2B6 (CYP2B6) SUBSTRATES Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, licorice might increase levels of drugs metabolized by CYP2B6.  Details In vitro research shows that licorice extract and glabridin, a licorice constituent, inhibit CYP2B6 isoenzymes (10300,94822). Licorice extract from the species G. uralensis seems to inhibit CYP2B6 isoenzymes to a greater degree than G. glabra extract in vitro (94822). Theoretically, these species of licorice might increase levels of drugs metabolized by CYP2B6; however, these interactions have not yet been reported in humans.

CYTOCHROME P450 2C19 (CYP2C19) SUBSTRATES Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, licorice might increase levels of drugs metabolized by CYP2C19.  Details In vitro, licorice extracts from the species G. glabra and G. uralensis inhibit CYP2C19 isoenzymes in vitro (94822). Theoretically, these species of licorice might increase levels of drugs metabolized by CYP2C19; however, this interaction has not yet been reported in humans.

CYTOCHROME P450 2C8 (CYP2C8) SUBSTRATES Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, licorice might increase levels of drugs metabolized by CYP2C8.  Details In vitro, licorice extract from the species G. glabra and G. uralensis inhibits CYP2C8 isoenzymes (94822). Theoretically, these species of licorice might increase levels of drugs metabolized by CYP2C8; however, this interaction has not yet been reported in humans.

CYTOCHROME P450 2C9 (CYP2C9) SUBSTRATES Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, licorice might increase or decrease levels of drugs metabolized by CYP2C9.  Details There is conflicting evidence about the effect of licorice on CYP2C9 enzyme activity. In vitro research shows that extracts from the licorice species G. glabra and G. uralensis moderately inhibit CYP2C9 isoenzymes (10300,94822). However, evidence from an animal model shows that licorice extract from the species G. uralensis can induce hepatic CYP2C9 activity (14441). Until more is known, licorice should be used cautiously in people taking CYP2C9 substrates.

CYTOCHROME P450 3A4 (CYP3A4) SUBSTRATES Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = B Theoretically, licorice might increase or decrease levels of drugs metabolized by CYP3A4.  Details Pharmacokinetic research shows that the licorice constituent glycyrrhizin, taken in a dosage of 150 mg orally twice daily for 14 days, modestly decreases the area under the concentration-time curve of midazolam by about 20%. Midazolam is a substrate of CYP3A4, suggesting that glycyrrhizin modestly induces CYP3A4 activity (59808). Animal research also shows that licorice extract from the species G. uralensis induces CYP3A4 activity (14441). However, licorice extract from G. glabra species appear to inhibit CYP3A4-induced metabolism of testosterone in vitro. It is thought that the G. glabra inhibits CYP3A4 due to its constituent glabridin, which is a moderate CYP3A4 inhibitor in vitro and not present in other licorice species (10300,94822). Until more is known, licorice should be used cautiously in people taking CYP3A4 substrates.

DIGOXIN (Lanoxin) Interaction Rating = Moderate Be cautious with this combination. Severity = High •  Occurrence = Possible •  Level of Evidence = D Theoretically, concomitant use of licorice with digoxin might increase the risk of cardiac toxicity.  Details Overuse or misuse of licorice with cardiac glycoside therapy might increase the risk of cardiac toxicity due to potassium loss (10393).

DIURETIC DRUGS Interaction Rating = Moderate Be cautious with this combination. Severity = High •  Occurrence = Possible •  Level of Evidence = D Theoretically, concomitant use of licorice with diuretic drugs might increase the risk of hypokalemia.  Details Overuse of licorice might compound diuretic-induced potassium loss (10393,20045,20046,59812). In one case report, a 72-year-old male with a past medical history of hypertension, type 2 diabetes, hyperlipidemia, arrhythmia, stroke, and hepatic dysfunction was hospitalized with severe hypokalemia and uncontrolled hypertension due to pseudohyperaldosteronism. This was thought to be provoked by concomitant daily consumption of a product containing 225 mg of glycyrrhizin, a constituent of licorice, and hydrochlorothiazide 12.5 mg for 1 month (108577).

ESTROGENS Interaction Rating = Moderate Be cautious with this combination. Severity = High •  Occurrence = Possible •  Level of Evidence = D Theoretically, licorice might increase or decrease the effects of estrogen therapy.  Details Theoretically, licorice might interfere with estrogen therapy due to estrogenic and anti-estrogenic effects (7860,16058).

LOOP DIURETICS Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, loop diuretics might increase the mineralocorticoid effects of licorice.  Details Theoretically, loop diuretics might enhance the mineralocorticoid effects of licorice by inhibiting the enzyme that converts cortisol to cortisone; however, bumetanide (Bumex) does not appear to have this effect (3255).

METHOTREXATE (Trexall, others) Interaction Rating = Minor Be watchful with this combination. Severity = Moderate •  Occurrence = Unlikely •  Level of Evidence = D Theoretically, licorice might increase levels of methotrexate.  Details Animal research suggests that intravenous administration of glycyrrhizin, a licorice constituent, and high-dose methotrexate may delay methotrexate excretion and increase systemic exposure, leading to transient elevations in liver enzymes and total bilirubin (108570). This interaction has not yet been reported in humans.

MIDAZOLAM (Versed) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = B Theoretically, licorice might decrease levels of midazolam.  Details In humans, the licorice constituent glycyrrhizin appears to moderately induce the metabolism of midazolam (59808). This is likely due to induction of cytochrome P450 3A4 by licorice. Until more is known, licorice should be used cautiously in people taking midazolam.

P-GLYCOPROTEIN SUBSTRATES Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, licorice might decrease the absorption of P-glycoprotein substrates.  Details In vitro research shows that licorice can increase P-glycoprotein activity (104561).

PACLITAXEL (Abraxane, Onxol) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, licorice might decrease plasma levels and clinical effects of paclitaxel.  Details Multiple doses of licorice taken concomitantly with paclitaxel might reduce the effectiveness of paclitaxel. Animal research shows that licorice 3 grams/kg given orally for 14 days before intravenous administration of paclitaxel decreases the exposure to paclitaxel and increases its clearance. Theoretically, this occurs because licorice induces cytochrome P450 3A4 enzymes, which metabolize paclitaxel. Notably, a single dose of licorice did not affect exposure or clearance of paclitaxel (102959).

WARFARIN (Coumadin) Interaction Rating = Moderate Be cautious with this combination. Severity = High •  Occurrence = Possible •  Level of Evidence = D Theoretically, licorice might decrease plasma levels and clinical effects of warfarin.  Details Licorice seems to increase metabolism and decrease levels of warfarin in animal models. This is likely due to induction of cytochrome P450 2C9 (CYP2C9) metabolism by licorice (14441). Advise patients taking warfarin to avoid taking licorice.

(Read more about LICORICE)

ANTIDIABETES DRUGS Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = B Taking milk thistle with antidiabetes drugs may increase the risk of hypoglycemia.  Details Clinical research shows that milk thistle extract, alone or along with tree turmeric extract, can lower blood glucose levels and glycated hemoglobin (HbA1c) in patients with type 2 diabetes, including those already taking antidiabetes drugs (15102,63190,63314,63318,95019,96140,96141,97624,97626,113987).

CYTOCHROME P450 2B6 (CYP2B6) SUBSTRATES Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, milk thistle might inhibit CYP2B6.  Details An in vitro study shows that silybin, a constituent of milk thistle, binds to and noncompetitively inhibits CYP2B6. Additionally, silybin might downregulate the expression of CYP2B6 by decreasing mRNA and protein levels (112229).

CYTOCHROME P450 2C9 (CYP2C9) SUBSTRATES Interaction Rating = Minor Be watchful with this combination. Severity = Mild •  Occurrence = Unlikely •  Level of Evidence = B It is unclear if milk thistle inhibits CYP2C9; research is conflicting.  Details In vitro research suggests that milk thistle might inhibit CYP2C9 (7089,17973,17976). Additionally, 3 case reports from the World Health Organization (WHO) adverse drug reaction database describe increased toxicity in patients taking milk thistle and cancer medications that are CYP2C9 substrates, including imatinib and capecitabine (111644). However, contradictory clinical research shows that milk thistle extract does not inhibit CYP2C9 or significantly affect levels of the CYP2C9 substrate tolbutamide (13712,95026). Differences in results could be due to differences in dosages or formulations utilized (95026).

CYTOCHROME P450 3A4 (CYP3A4) SUBSTRATES Interaction Rating = Minor Be watchful with this combination. Severity = Mild •  Occurrence = Unlikely •  Level of Evidence = D It is unclear if milk thistle inhibits CYP3A4; research is conflicting.  Details While laboratory research shows conflicting results (7318,17973,17975,17976), pharmacokinetic research shows that taking milk thistle extract 420-1350 mg daily does not significantly affect the metabolism of the CYP3A4 substrates irinotecan, midazolam, or indinavir (8234,17974,93578,95026). However, 8 case reports from the World Health Organization (WHO) adverse drug reaction database describe increased toxicity in patients taking milk thistle and cancer medications that are CYP3A4 substrates, including gefitinib, sorafenib, doxorubicin, and vincristine (111644).

ESTROGENS Interaction Rating = Minor Be watchful with this combination. Severity = Mild •  Occurrence = Possible •  Level of Evidence = D Theoretically, milk thistle might interfere with estrogen therapy through competition for estrogen receptors.  Details Animal research suggests that a milk thistle extract of silymarin binds to estrogen receptor beta (93025,93026).

GLUCURONIDATED DRUGS Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, milk thistle might affect the clearance of drugs that undergo glucuronidation.  Details Laboratory research shows that milk thistle constituents inhibit uridine diphosphoglucuronosyl transferase (UGT), the major phase 2 enzyme that is responsible for glucuronidation (7318,17973). Theoretically, this could decrease the clearance and increase levels of glucuronidated drugs. Other laboratory research suggests that a milk thistle extract of silymarin might inhibit beta-glucuronidase (7354), although the significance of this effect is unclear.

HMG-CoA REDUCTASE INHIBITORS ("Statins") Interaction Rating = Minor Be watchful with this combination. Severity = Mild •  Occurrence = Unlikely •  Level of Evidence = D Theoretically, milk thistle might interfere with statin therapy by decreasing the activity of organic anion transporting polypeptide 1B1 (OATB1B1) and inhibiting breast cancer resistance protein (BCRP).  Details Preliminary evidence suggests that a milk thistle extract of silymarin can decrease the activity of the OATP1B1, which transports HMG-CoA reductase inhibitors into the liver to their site of action, and animal research shows this increases the maximum plasma concentration of pitavastatin and pravastatin (113975). The silibinin component also inhibits BCRP, which transports statins from the liver into the bile for excretion. However, in a preliminary study in healthy males, silymarin 140 mg three times daily had no effect on the pharmacokinetics of a single 10 mg dose of rosuvastatin (16408).

INDINAVIR (Crixivan) Interaction Rating = Minor Be watchful with this combination. Severity = Mild •  Occurrence = Unlikely •  Level of Evidence = B Theoretically, milk thistle may induce cytochrome P450 3A4 (CYP3A4) enzymes and increase the metabolism of indinavir; however, results are conflicting.  Details One pharmacokinetic study shows that taking milk thistle (Standardized Milk Thistle, General Nutrition Corp.) 175 mg three times daily in combination with multiple doses of indinavir 800 mg every 8 hours decreases the mean trough levels of indinavir by 25% (8234). However, results from the same pharmacokinetic study show that milk thistle does not affect the overall exposure to indinavir (8234). Furthermore, two other pharmacokinetic studies show that taking specific milk thistle extract (Legalon, Rottapharm Madaus; Thisilyn, Nature's Way) 160-450 mg every 8 hours in combination with multiple doses of indinavir 800 mg every 8 hours does not reduce levels of indinavir (93578).

LEDIPASVIR Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, milk thistle might increase the levels and clinical effects of ledipasvir.  Details Animal research in rats shows that milk thistle increases the area under the curve (AUC) for ledipasvir and slows its elimination (109505).

MORPHINE Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, concomitant use of milk thistle with morphine might affect serum levels of morphine and either increase or decrease its effects.  Details Animal research shows that milk thistle reduces serum levels of morphine by up to 66% (101161). In contrast, laboratory research shows that milk thistle constituents inhibit uridine diphosphoglucuronosyl transferase (UGT), the major phase 2 enzyme that is responsible for glucuronidation (7318,17973). Theoretically, this could decrease the clearance and increase morphine levels. The effect of taking milk thistle on morphine metabolism in humans is not known.

ORGANIC ANION-TRANSPORTING POLYPEPTIDE SUBSTRATES (OATP) Interaction Rating = Minor Be watchful with this combination. Severity = Mild •  Occurrence = Possible •  Level of Evidence = D Milk thistle may inhibit one form of OATP, OATP-B1, which could reduce the bioavailability and clinical effects of OATP-B1 substrates.  Details In vitro research shows that milk thistle inhibits OATP-B1. Two case reports from the World Health Organization (WHO) adverse drug reaction database describe increased toxicity in patients taking milk thistle and cancer medications that are OATP substrates, including sorafenib and methotrexate (111644). OATPs are expressed in the small intestine and liver and are responsible for the uptake of drugs and other compounds into the body. Inhibition of OATP may reduce the bioavailability of oral drugs that are substrates of OATP.

P-GLYCOPROTEIN SUBSTRATES Interaction Rating = Minor Be watchful with this combination. Severity = Moderate •  Occurrence = Unlikely •  Level of Evidence = B Theoretically, milk thistle might increase the absorption of P-glycoprotein substrates. However, this effect does not seem to be clinically significant.  Details In vitro research shows that milk thistle can inhibit P-glycoprotein activity (95019,111644) and 1 case report from the World Health Organization (WHO) adverse drug reaction database describes increased abdominal pain in a patient taking milk thistle and the cancer medication vincristine, a P-glycoprotein substrate, though this patient was also taking methotrexate (111644). However, a small pharmacokinetic study in healthy volunteers shows that taking milk thistle (Enzymatic Therapy Inc.) 900 mg, standardized to 80% silymarin, in 3 divided doses daily for 14 days does not affect absorption of digoxin, a P-glycoprotein substrate (35825).

RALOXIFENE (Evista) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, milk thistle might decrease the clearance and increase levels of raloxifene.  Details Laboratory research suggests that the milk thistle constituents silibinin and silymarin inhibit the glucuronidation of raloxifene in the intestines (93024).

SIROLIMUS (Rapamune) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = B Milk thistle might decrease the clearance of sirolimus.  Details Pharmacokinetic research shows that a milk thistle extract of silymarin decreases the apparent clearance of sirolimus in hepatically impaired renal transplant patients (19876). It is unclear if this interaction occurs in patients without hepatic impairment.

SOFOSBUVIR (Solvaldi) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, milk thistle might decrease the levels and clinical effects of sofosbuvir.  Details Animal research in rats shows that milk thistle reduces the metabolism of sofosbuvir, as well as the hepatic uptake of its active metabolite (109505).

TAMOXIFEN (Nolvadex) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, the milk thistle constituent silibinin might increase tamoxifen levels and interfere with its conversion to an active metabolite.  Details Animal research suggests that the milk thistle constituent silibinin might increase plasma levels of tamoxifen and alter its conversion to an active metabolite. The mechanism appears to involve inhibition of pre-systemic metabolism of tamoxifen by cytochrome P450 (CYP) 2C9 and CYP3A4, and inhibition of P-glycoprotein-mediated efflux of tamoxifen into the intestine for excretion (17101). Whether this interaction occurs in humans is not known.

WARFARIN (Coumadin) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, milk thistle might increase the effects of warfarin.  Details In one case report, a man stabilized on warfarin experienced an increase in INR from 2.64 to 4.12 after taking a combination product containing milk thistle 200 mg daily, as well as dandelion, wild yam, niacinamide, and vitamin B12. Levels returned to normal after stopping the supplement (101159). Although a direct correlation between milk thistle and the change in INR cannot be confirmed, some in vitro research suggests that milk thistle might inhibit cytochrome P450 2C9 (CYP2C9), an enzyme involved in the metabolism of various drugs, including warfarin (7089,17973,17976).

(Read more about MILK THISTLE)

General ...Orally, artichoke extract seems to be well tolerated.
Most Common Adverse Effects:
Orally: Abdominal pain, diarrhea, flatulence, hunger, and nausea.
Topically: Contact dermatitis in sensitive individuals.
Serious Adverse Effects (Rare):
Orally: Anaphylaxis to artichoke inulin has been reported in individuals sensitive to inulin.
Topically: Chest tightness, cough, and dyspnea after occupational exposure in sensitive individuals.

Dermatologic ...Artichoke can cause an allergic reaction in some patients. Patients sensitive to the Asteraceae/Compositae family may be at the greatest risk. Members of this family include ragweed, chrysanthemums, marigolds, daisies, and many other herbs. Topically, allergic contact dermatitis can occur with the use of artichoke. This has been attributed to the constituent cynaropicrin (11,52206,52226,52230). Redness in the face (11774) and sweating (91475) have been reported rarely following oral use of artichoke extract.
Occupational or airborne exposure to artichoke may also cause allergic reactions. In one case, a 52-year-old male presented with severe spongiotic dermatitis in exposed areas that was recurrent over the past 8 years. A patch test confirmed allergies to artichokes and sesquiterpene lactones, a group of allergens from the Compositae family, and the patient confirmed occupational and airborne exposure to artichokes during the time of his symptoms. The patient improved considerably after treatment with dupilumab (111565).

Gastrointestinal ...Orally, artichoke extract might increase abdominal discomfort, flatulence, diarrhea, hunger, and nausea in some patients (2562,52238,91475). Abdominal pain and a bitter taste in the mouth were reported by a single person following oral use of a dietary supplement containing artichoke extract, as well as red yeast rice, pine bark extract, and garlic extract (89452). It is not clear if this adverse effect was due to artichoke, other ingredients, or the combination.
In one case report, the autopsy of an 84-year-old female revealed a colonic bezoar comprised of artichoke fiber and fragments. This bezoar caused complete intestinal obstruction, leading to fatal acute peritonitis. Although rare, patients who lack adequate teeth and/or who have a history of gastric surgery are at increased risk for fibrous bezoar formation (97716).

Pulmonary/Respiratory ...Following occupational exposure, allergic symptoms including dyspnea, cough, chest tightness, and asthma symptoms or exacerbation have been reported. The effects were attributed to sensitization to artichoke. Subsequent nasal challenge with artichoke extract caused reduced nasal patency in these patients (52210,52230).
Orally, severe anaphylactic shock in response to artichoke inulin as an ingredient in commercially available products has been reported (52217). Individuals with a noted sensitivity to artichokes should consume inulin with caution. While rare, individuals with a known inulin allergy should avoid artichoke and artichoke extract.

(Read more about ARTICHOKE)

General ...Orally, dandelion seems to be well tolerated.
Most Common Adverse Effects:
Orally: Diarrhea, heartburn, and stomach discomfort.
Topically: Dermatitis in sensitive individuals.
Serious Adverse Effects (Rare):
Orally: Anaphylaxis in sensitive individuals.

Cardiovascular ...In one report, a 39-year-old obese woman developed palpitations and syncope after taking a weight loss supplement containing a combination of dandelion, bladderwrack, and boldo for 3 weeks. The patient was found to have prolonged QT-interval on ECG and frequent episodes of sustained polymorphic ventricular tachycardia (14321). It is not clear whether dandelion, another ingredient, or the combination of ingredients is responsible for this adverse effect. The product was not analyzed to determine the presence of any potential toxic contaminants.

Dermatologic ...Topically, dandelion can cause contact dermatitis and erythema multiforme in sensitive individuals. Dandelion can cause an allergic reaction in individuals sensitive to the Asteraceae/Compositae family (13478,13481,42893,46945,46977). Members of this family include ragweed, chrysanthemums, marigolds, daisies, and many other herbs.

Endocrine ...In one report, a 56-year-old man with renal impairment developed hyperoxalaemia and peripheral gangrene after ingesting large amounts of dandelion tea (10 to 15 cups daily for 6 months). The adverse effect was attributed to the high oxalate content of dandelion tea (258 mcmol/L) and reduced renal oxalate clearance caused by renal impairment (90639). In another report, a 58-year-old woman with type 2 diabetes who was being treated with insulin developed hypoglycemic symptoms 2 weeks after beginning to eat salads containing dandelion (46960). The hypoglycemic effect was attributed to the potential alpha-glucosidase inhibitory activity of dandelion.

Gastrointestinal ...Gastrointestinal symptoms, including stomach discomfort, diarrhea, and heartburn, have been reported following oral use of dandelion (19146,36931). A case of intestinal blockage has been reported for a patient who ingested a large amount of dandelion greens three weeks after undergoing a stomach operation (46981). Also, a case of hemorrhagic cystitis has been reported for a 33-year-old woman who took a specific herbal product (Slim-Kombu, Balestra and Mech, Vicenza, Italy) containing 20 herbal extracts, including dandelion extract. Symptoms resolved after the patient discontinued using the product, and symptoms resumed when the patient began taking the supplement again four months later. While various ingredients in the supplement may have contributed to the symptoms, it is possible that dandelion extract may have contributed to the effect due to its diuretic, laxative, cholagogue, and antirheumatic properties (46959).

Other ...Orally, products containing dandelion pollen can cause allergic reactions, including anaphylaxis (13479,13480). Also, rhinoconjunctivitis and asthma have been reported after handling products such as bird feed containing dandelion and other herbs, with reported positive skin tests for dandelion hypersensitivity (46948). Dandelion pollen may cause pollinosis, such as allergic rhinitis and conjunctivitis (18065,46951,46964,46966,46972).

(Read more about DANDELION)

General ...Orally, licorice is generally well tolerated when used in amounts commonly found in foods. It seems to be well tolerated when licorice products that do not contain glycyrrhizin (deglycyrrhizinated licorice) are used orally and appropriately for medicinal purposes or when used topically, short-term.
Most Common Adverse Effects:
Orally: Headache, nausea, and vomiting.
Topically: Contact dermatitis.
Intravenously: Diarrhea, itching, nausea, and rash.
Serious Adverse Effects (Rare):
Orally: Case reports have raised concerns about acute renal failure, cardiac arrest, cardiac arrhythmias, hypertension, hypokalemia, muscle weakness, paralysis, pseudohyperaldosteronism, and seizure associated with long-term use or large amounts of licorice containing glycyrrhizin.

Cardiovascular ...Orally, excessive licorice ingestion can lead to pseudohyperaldosteronism, which can precipitate cardiovascular complications such as hypertension and hypertensive crisis, ventricular fibrillation or tachycardia, sinus pause, and cardiac arrest. These effects are due to the licorice constituent glycyrrhizin and usually occur when 20-30 grams or more of licorice product is consumed daily for several weeks (781,15590,15592,15594,15596,15597,15599,15600,16835,97213) (104563,108574,108576,110305,112234). In one case report, an 89-year-old female taking an herbal medicine containing licorice experienced a fatal arrhythmia secondary to licorice-induced hypokalemia. The patient presented to the hospital with recurrent syncope, weakness, and fatigue for 5 days after taking an herbal medicine containing licorice for 2 months. Upon admission to the hospital, the patient developed seizures, QT prolongation, and ventricular arrhythmia requiring multiple defibrillations. Laboratory tests confirmed hypokalemia and pseudohyperaldosteronism (112234).
However, people with cardiovascular or kidney conditions may be more sensitive, so these adverse events may occur with doses as low as 5 grams of licorice product or glycyrrhizin 100 mg daily (15589,15593,15598,15600,59726). A case report in a 54-year-old male suggests that malnutrition might increase the risk of severe adverse effects with excessive licorice consumption. This patient presented to the emergency room with cardiac arrest and ventricular fibrillation after excessive daily consumption of licorice for about 3 weeks. This caused pseudohyperaldosteronism and then hypokalemia, leading to cardiovascular manifestations. In spite of resuscitative treatment, the patient progressed to kidney failure, refused dialysis, and died shortly thereafter (103791).

Dermatologic ...There have been reports of contact allergy, resulting in an itchy reddish eruption, occurring in patients that applied cosmetic products containing oil-soluble licorice extracts (59912). There have also been at least 3 cases of allergic contact dermatitis reported with the topical application of glycyrrhizin-containing products to damaged skin. In one case report, a 31-year-old female with acne presented with a 2-year history of pruritic erythematous-scaly plaques located predominantly on the face and neck after the use of a cosmetic product containing licorice root extract 1%. The patient had a positive skin patch test to licorice root extract, leading the clinicians to hypothesize that the use of benzoyl peroxide, a strong irritant, might have sensitized the patient to licorice (108578). Burning sensation, itching, redness, and scaling were reported rarely in patients applying a combination of licorice, calendula, and snail secretion filtrate to the face. The specific role of licorice is unclear (110322).
In rare cases, the glycyrrhizin constituent of licorice has caused rash and itching when administered intravenously (59712).

Endocrine ...Orally, excessive licorice ingestion can cause a syndrome of apparent mineralocorticoid excess, or pseudohyperaldosteronism, with sodium and water retention, increased urinary potassium loss, hypokalemia, and metabolic alkalosis due to its glycyrrhizin content (781,10619,15591,15592,15593,15594,15595,15596,15597,15598)(15600,16057,16835,25659,25660,25673,25719,26439,59818,59822)(59832,59864,91722,104563,108568,108574,110305,112234). These metabolic abnormalities can lead to hypertension, edema, EKG changes, fatigue, syncope, arrhythmias, cardiac arrest, headache, lethargy, muscle weakness, dropped head syndrome (DHS), rhabdomyolysis, myoglobinuria, paralysis, encephalopathy, respiratory impairment, hyperparathyroidism, and acute kidney failure (10393,10619,15589,15590,15593,15594,15596,15597,15599)(15600,16057,16835,25660,25673,25719,26439,31562,59709,59716)(59720,59740,59787,59820,59826,59882,59889,59900,91722,97214,100522) (104563,108576,108577). These effects are most likely to occur when 20-30 grams of licorice products containing glycyrrhizin 400 mg or more is consumed daily for several weeks (781,15590,15592,15594,15596,15597,15599,15600,16835,108574). However, some people may be more sensitive, especially those with hypertension, diabetes, heart problems, or kidney problems (15589,15593,15598,15600,59726,108576,108577) and even low or moderate consumption of licorice may cause hypertensive crisis or hypertension in normotensive individuals (1372,97213). The use of certain medications with licorice may also increase the risk of these adverse effects (108568,108577). One case report determined that the use of large doses of licorice in an elderly female stabilized on fludrocortisone precipitated hypokalemia and hypertension, requiring inpatient treatment (108568). Another case report describes severe hypokalemia necessitating intensive care treatment due to co-ingestion of an oral glycyrrhizin-specific product and hydrochlorothiazide for 1 month (108577). Glycyrrhetinic acid has a long half-life, a large volume of distribution, and extensive enterohepatic recirculation. Therefore, it may take 1-2 weeks before hypokalemia resolves (781,15595,15596,15597,15600). Normalization of the renin-aldosterone axis and blood pressure can take up to several months (781,15595,108568). Treatment typically includes the discontinuation of licorice, oral and intravenous potassium supplementation, and short-term use of aldosterone antagonists, such as spironolactone (108574,108577).
Chewing tobacco flavored with licorice has also been associated with toxicity. Chewing licorice-flavored tobacco, drinking licorice tea, or ingesting large amounts of black licorice flavored jelly beans or lozenges has been associated with hypertension and suppressed renin and aldosterone levels (12671,12837,97214,97215,97217,108574). One case report suggests that taking a combination product containing about 100 mg of licorice and other ingredients (Jintan, Morishita Jintan Co.) for many decades may be associated with hypoaldosteronism, even up to 5 months after discontinuation of the product (100522). In another case report, licorice ingestion led to hyperprolactinemia in a female (59901). Licorice-associated hypercalcemia has also been noted in a case report (59766).

Gastrointestinal ...Nausea and vomiting have been reported rarely following oral use of deglycyrrhizinated licorice (25694,59871). Intravenously, the glycyrrhizin constituent of licorice has rarely caused gastric discomfort, diarrhea, or nausea (59712,59915).

Immunologic ...There have been reports of contact allergy, resulting in an itchy reddish eruption, occurring in patients that applied cosmetic products containing oil-soluble licorice extracts (59912). There have also been at least 3 cases of allergic contact dermatitis reported with the topical application of glycyrrhizin-containing products to damaged skin. In one case report, a 31-year-old female with acne presented with a 2-year history of pruritic erythematous-scaly plaques located predominantly on the face and neck after the use of a cosmetic product containing licorice root extract 1%. The patient had a positive skin patch test to licorice root extract, leading the clinicians to hypothesize that the use of benzoyl peroxide, a strong irritant, might have sensitized the patient to licorice (108578).

Musculoskeletal ...In a case report, excessive glycyrrhizin-containing licorice consumption led to water retention and was thought to trigger neuropathy and carpal tunnel syndrome (59791).

Neurologic/CNS ...Orally, licorice containing larger amounts of glycyrrhizin may cause headaches. A healthy woman taking glycyrrhizin 380 mg daily for 2 weeks experienced a headache (59892). Intravenously, the glycyrrhizin constituent of licorice has rarely caused headaches or fatigue (59721). In a case report, licorice candy ingestion was associated with posterior reversible encephalopathy syndrome accompanied by a tonic-clonic seizure (97218).

Ocular/Otic ...Orally, consuming glycyrrhizin-containing licorice 114-909 grams has been associated with transient visual loss (59714).

Pulmonary/Respiratory ...Orally, large amounts of licorice might lead to pulmonary edema. In one case report, a 64-year old male consumed 1020 grams of black licorice (Hershey Twizzlers) containing glycyrrhizin 3.6 grams over 3 days, which resulted in pulmonary edema secondary to pseudohyperaldosteronism (31561). Intravenously, the glycyrrhizin constituent of licorice has caused cold or flu-like symptoms, although these events are not common (59712,59721).

(Read more about LICORICE)

General ...Orally, milk thistle is well tolerated.
Most Common Adverse Effects:
Orally: Abdominal bloating, diarrhea, dyspepsia, flatulence, and nausea. However, these adverse effects do not typically occur at a greater frequency than with placebo.
Serious Adverse Effects (Rare):
Orally: Allergic reactions, including anaphylaxis, have been reported.

Dermatologic ...Orally, milk thistle may cause allergic reactions including urticaria, eczema, skin rash, and anaphylaxis in some people (6879,7355,8956,63210,63212,63238,63251,63315,63325,95029). Allergic reactions may be more likely to occur in patients sensitive to the Asteraceae/Compositae family (6879,8956). A case report describes a 49-year-old female who developed clinical, serologic, and immunopathologic features of bullous pemphigoid after taking milk thistle orally for 6 weeks. Symptoms resolved after treatment with prednisone and methotrexate (107376). Topically, milk thistle can cause erythema (110489).

Gastrointestinal ...Mild gastrointestinal symptoms have been reported, including nausea, vomiting, bloating, diarrhea, epigastric pain, abdominal colic or discomfort, dyspepsia, dysgeusia, flatulence, constipation, and loss of appetite (2616,6879,8956,13170,63140,63146,63160,63210,63218,63219)(63221,63244,63247,63250,63251,63320,63321,63323,63324,63325)(63327,63328,95024,95029,107374). There is one report of a 57-year-old female with sweating, nausea, colicky abdominal pain, diarrhea, vomiting, weakness, and collapse after ingesting milk thistle; symptoms subsided after 24-48 hours without medical treatment and recurred with re-challenge (63329).

Musculoskeletal ...In one clinical study three patients taking milk thistle 200 mg orally three times daily experienced tremor; the incidence of this adverse effect was similar for patients treated with fluoxetine 10 mg three times daily (63219).

(Read more about MILK THISTLE)