Angelica root • Gentian root • Oregon Grape root • Bayberry root bark • fennel seed • Prickly Ash bark • Ginger root.
Brand name products often contain multiple ingredients. To read detailed information about each ingredient, click on the link for the individual ingredient shown above.
Below is general information about the effectiveness of the known ingredients contained in the product Gest Tonic. Some ingredients may not be listed. This information does NOT represent a recommendation for or a test of this specific product as a whole.
INSUFFICIENT RELIABLE EVIDENCE to RATE
There is insufficient reliable information available about the effectiveness of bayberry.
INSUFFICIENT RELIABLE EVIDENCE to RATE
INSUFFICIENT RELIABLE EVIDENCE to RATE
INSUFFICIENT RELIABLE EVIDENCE to RATE
There is insufficient reliable information available about the effectiveness of Hercules club.
There is insufficient reliable information available about the effectiveness of northern prickly ash.
INSUFFICIENT RELIABLE EVIDENCE to RATE
Below is general information about the safety of the known ingredients contained in the product Gest Tonic. Some ingredients may not be listed. This information does NOT represent a recommendation for or a test of this specific product as a whole.
LIKELY SAFE ...when used orally in amounts commonly found in foods. Angelica archangelica has Generally Recognized as Safe (GRAS) status in the US (4912). There is insufficient reliable information available about the safety of Angelica archangelica when used orally or topically for medicinal purposes.
PREGNANCY AND LACTATION:
Insufficient reliable information available; avoid using.
POSSIBLY UNSAFE ...when used orally. The root, bark, and berries contain high amounts of tannins (6). Large doses may have mineralocorticoid activity (4). The root bark can also contain a carcinogen (5). There is insufficient reliable information available about the safety of bayberry for its other uses.
PREGNANCY AND LACTATION: POSSIBLY UNSAFE
when used orally or topically because of possible carcinogenic, or mineralocorticoid activities; avoid using (4,5).
LIKELY SAFE ...when used orally in amounts commonly found in foods. Fennel has Generally Recognized as Safe (GRAS) status in the US (4912).
POSSIBLY SAFE ...when fennel essential oil or extract is used orally and appropriately, short-term. Twenty-five drops (about 1.25 mL) of fennel fruit extract standardized to fennel 2% essential oil has been safely used four times daily for 5 days (49422). Also, two 100 mg capsules each containing fennel 30% essential oil standardized to 71-90 mg of anethole has been safely used daily for 8 weeks (97498). Powdered fennel extract has been used with apparent safety at a dose of 800 mg daily for 2 weeks (104199). ...when creams containing fennel 2% to 5% are applied topically (49429,92509).
CHILDREN: POSSIBLY SAFE
when combination products containing fennel are used to treat colic in infants for up to one week.
Studied products include up to 20 mL of a fennel seed oil emulsion; a specific product (ColiMil) containing fennel 164 mg, lemon balm 97 mg, and German chamomile 178 mg; and up to 450 mL of a specific tea (Calma-Bebi, Bonomelli) containing fennel, chamomile, vervain, licorice, and lemon balm (16735,19715,49428).
PREGNANCY: POSSIBLY UNSAFE
when used orally.
Observational research has found that regular use of fennel during pregnancy is associated with shortened gestation (100513).
LACTATION: POSSIBLY UNSAFE
when used orally.
Case reports have linked consumption of an herbal tea containing extracts of fennel, licorice, anise, and goat's rue to neurotoxicity in two breast-feeding infants. The adverse effect was attributed to anethole, a constituent of fennel and anise (16744). However, levels of anethole were not measured in breastmilk, and the herbal tea was not tested for contaminants. Furthermore, other adverse effects related to use of fennel during lactation have not been reported. However, until more is known, avoid using.
LIKELY SAFE ...when the root preparations are used in amounts commonly found in foods. Gentian root is categorized by the FDA as a safe food additive flavoring in the US (4912).
POSSIBLY SAFE ...when gentian root is used orally in a specific combination that contains gentian root, elderflower, verbena, cowslip flower, and sorrel (SinuComp, Sinupret) (374,379,95907). There is insufficient reliable information available about the safety of the topical use of gentian.
PREGNANCY AND LACTATION:
There is insufficient reliable information available about the safety of gentian in medicinal amounts during pregnancy and lactation; avoid using.
LIKELY SAFE ...when used orally and appropriately. Ginger has been safely used in multiple clinical trials (721,722,723,5343,7048,7084,7085,7400,7623,11346)(12472,13080,13237,13244,17369,17928,17929,89889,89890,89894)(89895,89898,89899,90102,96252,96253,96259,96260,96669) (101760,101761,101762,103359,107903).
POSSIBLY SAFE ...when used topically and appropriately, short-term (89893,89897).
CHILDREN: LIKELY SAFE
when consumed in the amounts typically found in foods.
CHILDREN: POSSIBLY SAFE
when used orally and appropriately, short-term.
Ginger powder has been used with apparent safety at a dose of up to 750 mg daily for 4 days in girls aged 14-18 years (96255).
PREGNANCY: LIKELY SAFE
when consumed in the amounts typically found in foods.
Ginger is considered a first-line nonpharmacological treatment option for nausea in pregnancy by the American College of Obstetrics and Gynecology (ACOG) (111601). However, it should not be used long-term or without medical supervision and close monitoring.
PREGNANCY: POSSIBLY SAFE
when used for medicinal purposes.
Despite some early reports of adverse effects (721,7083) and one observational study suggesting that taking dried ginger and other herbal supplements during the first 20 weeks of pregnancy marginally increased the chance of stillbirth (96254), most research shows that ginger is unlikely to cause harm to the baby. The risk for major malformations in infants of parents who took ginger when pregnant does not appear to be higher than the baseline rate of 1% to 3% (721,1922,5343,11346,13071,13080,96254). Also, other research suggests that ginger intake during various trimesters does not significantly affect the risk of spontaneous abortion, congenital malformations, stillbirth, perinatal death, preterm birth, low birth weight, or low Apgar scores (18211,90103). Ginger use has been associated with an increase in non-severe vaginal bleeding, including spotting, after week 17 of pregnancy (18211).
LACTATION: LIKELY SAFE
when consumed in the amounts typically found in foods.
There is insufficient reliable information available about the safety of ginger when used for medicinal purposes; avoid amounts greater than those found in foods.
There is insufficient reliable information available about the safety of Hercules club when used orally.
PREGNANCY: LIKELY UNSAFE
when used orally (12) because it might have menstrual stimulant effects (19).
There is insufficient reliable information available about the safety of the berry during pregnancy; avoid using.
LACTATION: POSSIBLY UNSAFE
when used orally because it might cause colic in nursing infants (19).
There is insufficient reliable information available about the safety of northern prickly ash when used orally.
PREGNANCY: POSSIBLY UNSAFE
when the bark is used orally (12); avoid using.
There is insufficient reliable information available about the safety of the berry or root during pregnancy; avoid using.
LACTATION:
Insufficient reliable information available; avoid using.
LIKELY SAFE ...when used orally in amounts commonly found in food.
POSSIBLY SAFE ...when used topically and appropriately (854,856,857,14000,14333). A specific 10% Oregon grape cream (Relieva, Apollo Pharmaceutical) has been used with apparent safety in studies lasting up to 12 weeks (14000,14333). There is insufficient reliable information available about the safety of Oregon grape when used orally in medicinal amounts.
CHILDREN: LIKELY UNSAFE
when used orally in newborns.
The berberine constituent of Oregon grape can cause kernicterus in newborns, particularly preterm neonates with hyperbilirubinemia (2589).
PREGNANCY: LIKELY UNSAFE
when used orally.
Berberine, a constituent of Oregon grape, is thought to cross the placenta and may cause harm to the fetus. Kernicterus has developed in newborn infants exposed to berberine (2589).
LACTATION: LIKELY UNSAFE
when used orally.
Berberine and other harmful constituents can be transferred to the infant through breast milk (2589).
Below is general information about the interactions of the known ingredients contained in the product Gest Tonic. Some ingredients may not be listed. This information does NOT represent a recommendation for or a test of this specific product as a whole.
Theoretically, fennel might increase the risk of bleeding when used with antiplatelet or anticoagulant drugs.
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Theoretically, fennel might decrease the levels and clinical effects of ciprofloxacin.
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Animal research shows that fennel reduces ciprofloxacin bioavailability by nearly 50%, possibly due to the metal cations such as calcium, iron, and magnesium contained in fennel. This study also found that fennel increased tissue distribution and slowed elimination of ciprofloxacin (6135). |
Theoretically, taking large amounts of fennel might decrease the effects of contraceptive drugs due to competition for estrogen receptors.
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Theoretically, fennel might increase levels of drugs metabolized by CYP3A4.
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Theoretically, taking large amounts of fennel might interfere with hormone replacement therapy due to competition for estrogen receptors.
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Theoretically, taking large amounts of fennel might decrease the antiestrogenic effect of tamoxifen.
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Some constituents of fennel have estrogenic activity (11), which may interfere with the antiestrogenic activity of tamoxifen. |
Theoretically, taking gentian with antihypertensive drugs might increase the risk of hypotension.
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Ginger may have antiplatelet effects and may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs. However, research is conflicting.
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Laboratory research suggests that ginger inhibits thromboxane synthetase and decreases platelet aggregation (7622,12634,20321,20322,20323,96257). However, this has not been demonstrated unequivocally in humans, with mixed results from clinical trials (96257). Theoretically, excessive amounts of ginger might increase the risk of bleeding when used with anticoagulant/antiplatelet drugs.
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Theoretically, taking ginger with antidiabetes drugs might increase the risk of hypoglycemia.
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Theoretically, taking ginger with calcium channel blockers might increase the risk of hypotension.
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Some animal and in vitro research suggests that ginger has hypotensive and calcium channel-blocking effects (12633). Another animal study shows that concomitant administration of ginger and the calcium channel blocker amlodipine leads to greater reductions in blood pressure when compared with amlodipine alone (107901).
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Theoretically, when taken prior to cyclosporine, ginger might decrease cyclosporine levels.
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In an animal model, ginger juice taken 2 hours prior to cyclosporine administration reduced the maximum concentration and area under the curve of cyclosporine by 51% and 40%, respectively. This effect was not observed when ginger juice and cyclosporine were administered at the same time (20401).
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Theoretically, ginger might increase the levels of CYP1A2 substrates.
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In vitro research shows that ginger inhibits CYP1A2 activity (111544). However, this interaction has not been reported in humans.
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Theoretically, ginger might increase the levels of CYP2B6 substrates.
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In vitro research shows that ginger inhibits CYP2B6 activity (111544). However, this interaction has not been reported in humans.
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Theoretically, ginger might increase the levels of CYP2C9 substrates.
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In vitro research shows that ginger inhibits CYP2C9 activity (111544). However, this interaction has not been reported in humans.
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Ginger might increase or decrease the levels of CYP3A4 substrates.
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In vitro research and some case reports suggest that ginger inhibits CYP3A4 activity (111544,111644). Three case reports from the World Health Organization (WHO) adverse drug reaction database describe increased toxicity in patients taking ginger and cancer medications that are CYP3A4 substrates (imatinib, dabrafenib, and crizotinib). However, the causality of this interaction is unclear due to the presence of multiple interacting drugs and routes of administration (111644).
Conversely, other in vitro research suggests that ginger induces CYP3A4 activity, leading to reduced levels of CYP3A4 substrates (111404). However, this interaction has not been reported in humans. |
Theoretically, ginger might increase levels of losartan and the risk of hypotension.
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In animal research, ginger increased the levels and hypotensive effects of a single dose of losartan (102459). It is not clear if ginger alters the concentration or effects of losartan when taken continuously. Additionally, this interaction has not been shown in humans.
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Theoretically, ginger might increase levels of metronidazole.
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In an animal model, ginger increased the absorption and plasma half-life of metronidazole. In addition, the elimination rate and clearance of metronidazole was significantly reduced (20350).
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Ginger may have antiplatelet effects and increase the risk of bleeding if used with nifedipine.
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Clinical research shows that combined treatment with ginger 1 gram plus nifedipine 10 mg significantly inhibits platelet aggregation when compared to nifedipine or ginger alone (20324).
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Ginger might increase the absorption and blood levels of P-glycoprotein (P-gp) substrates.
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In vitro research and case reports suggest that ginger inhibits drug efflux by P-gp, potentially increasing absorption and serum levels of P-gp substrates (111544,111644). Two case reports from the World Health Organization (WHO) adverse drug reaction database describe increased toxicity in patients taking ginger and cancer medications that are P-gp substrates (trametinib, crizotinib). However, the causality of this interaction is unclear due to the presence of multiple interacting drugs and routes of administration (111644).
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Ginger might increase the risk of bleeding with phenprocoumon.
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Phenprocoumon, a warfarin-related anticoagulant, might increase the international normalized ratio (INR) when taken with ginger. There is one case report of a 76-year-old woman with a stable INR on phenprocoumon that increased to greater than 10 when she began consuming dried ginger and ginger tea (12880).
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Ginger might increase the risk of bleeding with warfarin.
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Laboratory research suggests that ginger might inhibit thromboxane synthetase and decrease platelet aggregation (7622,12634,20321,20322,20323). In one case report, ginger increased the INR when taken with phenprocoumon, which has similar pharmacological effects as warfarin (12880). In another case report, ginger increased the INR when taken with a combination of warfarin, hydrochlorothiazide, and acetaminophen (20349). A longitudinal analysis suggests that taking ginger increases the risk of bleeding in patients taking warfarin for at least 4 months (20348). However, research in healthy people suggests that ginger has no effect on INR, or the pharmacokinetics or pharmacodynamics of warfarin (12881,15176). Until more is known, monitor INRs closely in patients taking large amounts of ginger.
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Theoretically, Hercules club may decrease the clinical effects of antacids.
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Due to reports that Hercules club increases stomach acid, Hercules club might decrease the effectiveness of antacids (19).
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Theoretically, Hercules club may decrease the clinical effects of H2 blockers.
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Due to reports that Hercules club increases stomach acid, Hercules club might decrease the effectiveness of H2-blockers (19).
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Theoretically, Hercules club may decrease the clinical effects of PPIs.
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Due to reports that Hercules club increases stomach acid, Hercules club might decrease the effectiveness of PPIs (19).
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Theoretically, northern prickly ash might decrease the effectiveness of antacids.
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There are reports that northern prickly ash increases stomach acid (19).
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Theoretically, northern prickly ash might decrease the effectiveness of H2-blockers.
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There are reports that northern prickly ash increases stomach acid (19).
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Theoretically, northern prickly ash might decrease the effectiveness of PPIs.
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There are reports that northern prickly ash increases stomach acid (19).
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Theoretically, Oregon grape might increase the risk of bleeding when taken with anticoagulant or antiplatelet drugs.
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Theoretically, Oregon grape might increase the risk of hypoglycemia when taken with antidiabetes drugs.
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Theoretically, Oregon grape might increase the risk of hypotension when taken with antihypertensive drugs.
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Animal research suggests that berberine, a constituent of Oregon grape, can have hypotensive effects (33692,34308). Also, an analysis of clinical evidence suggests that taking berberine in combination with amlodipine (Norvasc) can lower systolic and diastolic blood pressure when compared with taking amlodipine alone (91956).
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Theoretically, Oregon grape might increase the sedative effects of CNS depressants.
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Theoretically, Oregon grape might increase the effects and adverse effects of cyclosporine.
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Berberine, a constituent of Oregon grape, can reduce metabolism of cyclosporine and increase serum levels. It might inhibit cytochrome P450 3A4 (CYP3A4), which metabolizes cyclosporine (13524).
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Theoretically, Oregon grape might increase serum levels of drugs metabolized by CYP2C9.
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Preliminary clinical evidence suggests that berberine, a constituent of Oregon grape, can inhibit cytochrome P450 2C9 (CYP2C9) (34279).
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Theoretically, Oregon grape might increase serum levels of drugs metabolized by CYP2D6.
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Theoretically, Oregon grape might increase serum levels of drugs metabolized by CYP3A4.
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Theoretically, Oregon grape might increase serum levels of drugs that are P-glycoprotein (P-gp) substrates.
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In vitro research suggests that Oregon grape extracts inhibit P-gp efflux (112342).
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Below is general information about the adverse effects of the known ingredients contained in the product Gest Tonic. Some ingredients may not be listed. This information does NOT represent a recommendation for or a test of this specific product as a whole.
General
...Orally, Angelica archangelica is generally well tolerated in food amounts.
There is limited information available about the adverse effects of Angelica archangelica when used as medicine.
Most Common Adverse Effects:
Orally: Constipation, photosensitivity.
Dermatologic ...Orally or topically, Angelica archangelica might cause photosensitivity reactions (13406). Patients who take Angelica archangelica orally or apply it topically should be advised to avoid prolonged exposure to the sun. Some constituents of the leaves have a strong irritant effect on the skin and mucous membranes, referred to as "angelica dermatitis" (18).
Gastrointestinal ...Orally, Angelica archangelica has been reported to cause constipation in one out of 21 patients taking a specific Angelica archangelica leaf extract (SagaPro, SagaMedica) (92461).
General ...Orally, bayberry can cause gastrointestinal irritation, vomiting, and liver damage, possibly due to its tannin content. It can also act as an irritant and sensitizer (6).
Dermatologic ...Orally, bayberry can act as an irritant and sensitizer (6).
Gastrointestinal ...Orally, bayberry can cause gastrointestinal irritation and vomiting, possibly due to its tannin content (6).
Hepatic ...Orally, bayberry can cause liver damage, possibly due to its tannin content (6).
Immunologic ...Airborne bayberry pollen is a common cause of allergic respiratory symptoms (33888,33916).
Pulmonary/Respiratory ...Airborne bayberry pollen is a common cause of allergic respiratory symptoms (33888,33916).
General
...Orally and topically, fennel seems to be well tolerated.
Most Common Adverse Effects:
Orally: Gastrointestinal discomfort, photosensitivity, and allergic reactions in sensitive individuals.
Serious Adverse Effects (Rare):
Orally: Seizures.
Dermatologic ...Advise patients to avoid excessive sunlight or ultraviolet light exposure while using fennel (19). Allergic reactions affecting the skin such as atopic dermatitis and photosensitivity may occur in patients who consume fennel (6178,49507).
Gastrointestinal ...Orally, fennel may cause gastrointestinal complaints, including nausea and vomiting (19146,104196).
Hematologic ...Methemoglobinemia has been reported in four infants following intoxication related to ingestion of a homemade fennel puree that may have been made from improperly stored fennel (49444).
Immunologic ...A case report describes an 11-year-old male who developed an allergy to fennel-containing toothpaste. Immediately after using the toothpaste, the patient experienced sneezing, coughing, itchy mouth, rhinorrhea, nasal congestion, wheezing, difficulty breathing, and palpitations, which resolved within 10 minutes of spitting out the toothpaste and rinsing the mouth. In challenge tests, the patient reacted to chewing fresh fennel root, but not ground fennel seeds (103822).
Neurologic/CNS ...Orally, fennel oil has been associated with tonic clonic and generalized seizures (12868). New-onset cluster headaches are reported in a 24-year-old female while using a toothpaste containing fennel and camphor for 3 months. The headaches resolved upon stopping the toothpaste (112368). It is unclear if this adverse effect can be attributed to fennel, camphor, or the combination.
Pulmonary/Respiratory ...Orally, fennel and fennel seed have been reported to cause bronchial asthma (49478).
General
...Orally, gentian root, in combination with other herbs, seems to be generally well tolerated.
There is insufficient reliable information available about the adverse effects of gentian when taken as a medicine alone.
Most Common Adverse Effects:
Orally: Allergic skin reactions, gastrointestinal discomfort.
Gastrointestinal ...Orally, gentian root, in combination with other herbs, has been reported to cause gastrointestinal adverse effects (374,379). Gastrointestinal intolerance occurred in patients with cancer-associated anorexia who took gentian tincture 1 mL three times daily, in conjunction with turmeric 1 gram and ginger 1 gram twice daily, for 14 days. Six of 17 patients discontinued the regimen due to nausea, 3 due to vomiting, 2 due to diarrhea, and 2 due to bloating. It is unclear if this gastrointestinal intolerance was caused by gentian, the other herbs, or the patients' predisposing conditions (96263).
Immunologic ...Orally, gentian root, in combination with other herbs, has been reported to cause allergic skin reactions (374,379). It is unclear if these reactions were caused by gentian, the other herbs, or the combination.
General
...Orally, ginger is generally well tolerated.
However, higher doses of 5 grams per day increase the risk of side effects and reduce tolerability. Topically, ginger seems to be well tolerated.
Most Common Adverse Effects:
Orally: Abdominal discomfort, burping, diarrhea, heartburn, and a pepper-like irritant effect in the mouth and throat. However, some of these mild symptoms may be reduced by ingesting encapsulated ginger in place of powdered ginger.
Topically: Dermatitis in sensitive individuals.
Cardiovascular ...Orally, use of ginger resulted in mild arrhythmia in one patient in a clinical trial (16306).
Dermatologic
...Orally, ginger can cause hives (17933), as well as bruising and flushing (20316) or rash (20316).
Topically, ginger can cause dermatitis in sensitive individuals (12635,46902).
Gastrointestinal
...Orally, common side effects of ginger include nausea (17933,22602,89898,101761), belching (10380,103359), dry mouth (103359), dry retching (10380), vomiting (10380), burning sensation (10380), oral numbness (22602), abdominal discomfort (5343,89898,96253), heartburn (5343,7624,12472,16306,20316,51845,89894,89895,89898,89899)(101760,101761,101762,111543), diarrhea (5343,101760), constipation (89898,101760,101761), or a transient burning or "chilly hot" sensation of the tongue and throat (52076).
Orally, Number Ten, a specific product composed of rhubarb, ginger, astragalus, red sage, and turmeric, can increase the incidence of loose stools (20346).
Four cases of small bowel obstruction due to ginger bolus have been reported following the ingestion of raw ginger without sufficient mastication (chewing). In each case, the bolus was removed by enterotomy. Ginger is composed of cellulose and therefore is resistant to digestion. It can absorb water, which may cause it to swell and become lodged in narrow areas of the digestive tract (52115).
Genitourinary ...In one clinical trial, some patients reported increased menstrual bleeding while taking a specific ginger extract (Zintoma, Goldaru) 250 mg four times daily orally for 3 days (17931). An "intense" urge to urinate after 30 minutes was reported in two of eight patients given 0.5-1 gram of ginger (7624). However, this effect has not been corroborated elsewhere. Dysuria, flank pain, perineal pain, and urinary stream interruption have been reported in a 43-year-old male who drank ginger tea, containing 2-3 teaspoons of dry ginger, daily over 15 years. The adverse effects persisted for 4 years and were not associated with increases in urinary frequency or urgency. Upon discontinuing ginger, the patient's symptoms began to improve within one week and completely resolved after eight weeks, with no relapses six months later (107902).
Immunologic ...In one case report, a 59-year-old Japanese female with multiple allergic sensitivities developed pruritus and then anaphylactic shock after taking an oral ginger-containing herbal supplement for motion sickness (Keimei Gashinsan, Keimeido). The patient had used this supplement previously for over 20 years with no allergic reaction. The authors theorized the development of a cross-reactivity to ginger after the use of an oral supplement containing zedoary and turmeric, which are also in the Zingiberaceae family (102463).
Neurologic/CNS ...Orally, ginger may cause sedation, drowsiness, or dizziness (16306,17933,51845).
General ...None reported; however, a thorough evaluation of safety outcomes has not been conducted.
General ...There is limited reliable information available on the safety of northern prickly ash. A thorough evaluation of safety outcomes has not been conducted.
General ...Orally, no adverse effects have been reported. However, a thorough evaluation of safety outcomes has not been conducted. Topically, Oregon grape seems to be well tolerated.
Dermatologic ...Topically, Oregon grape may cause itching, burning, and skin irritation in some patients (854,14000).
Immunologic ...Topically, Oregon grape may cause allergic skin reactions in some patients (854,14000).
