Each vegetable capsule contains: Corydalis root 80 mg • White Peony Root 80 mg • Licorice root 80 mg • Black Cohosh 80 mg • Cramp Bark 40 mg • Cayenne fruit (40,000 HU) 40 mg • Ginger root 40 mg • Lobelia herb 40 mg • Red Clover 40 mg.
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 Flexaherb. 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
INSUFFICIENT RELIABLE EVIDENCE to RATE
INSUFFICIENT RELIABLE EVIDENCE to RATE
INSUFFICIENT RELIABLE EVIDENCE to RATE
INSUFFICIENT RELIABLE EVIDENCE to RATE
INSUFFICIENT RELIABLE EVIDENCE to RATE
INSUFFICIENT RELIABLE EVIDENCE to RATE
INSUFFICIENT RELIABLE EVIDENCE to RATE
Below is general information about the safety of the known ingredients contained in the product Flexaherb. Some ingredients may not be listed. This information does NOT represent a recommendation for or a test of this specific product as a whole.
POSSIBLY SAFE ...when used orally and appropriately. Black cohosh has been safely used in some studies lasting up to a year (15036,15158,17091,19553,35908); however, most studies have lasted only up to 6 months (141,4614,4620,7054,9437,9494,13143,13184,14330,14423)(14424,15037,15889,15893,35824,35852,35853,35858,35865,35897)(35902,35904,35946,35964,95525,103269). There is concern that black cohosh might cause liver damage in some patients. Several case reports link black cohosh to liver failure or autoimmune hepatitis (4383,10692,11906,12006,13144,14469,15160,16721,16722,16723)(16724,16725,16726,16727,35857,107906). However, the evidence that black cohosh causes liver damage is not conclusive (17085). Until more is known, monitor liver function in patients who take black cohosh.
PREGNANCY: POSSIBLY UNSAFE
when used orally in pregnant patients who are not at term.
Black cohosh might have hormonal effects and menstrual and uterine stimulant effects (15035). Theoretically, this might increase the risk of miscarriage; avoid using during pregnancy. There is insufficient reliable information available about the safety of black cohosh when used to induce labor.
LACTATION: POSSIBLY UNSAFE
when used orally.
Black cohosh might have hormonal effects. Theoretically, maternal intake of black cohosh might adversely affect a nursing child (15035). Until more is known, nursing patients should avoid taking black cohosh.
LIKELY SAFE ...when used orally in amounts typically found in food. Capsicum has Generally Recognized as Safe (GRAS) status in the US (4912). ...when used topically and appropriately (7038,10650,105345). The active capsicum constituent capsaicin is an FDA-approved ingredient used in certain over-the-counter, topical preparations (272).
POSSIBLY SAFE ...when used orally and appropriately, short-term in medicinal amounts. A specific sustained-release chili extract (Capsifen) has been used safely in doses of up to 200 mg daily, for up to 28 days (105196). ...when used intranasally and appropriately, short-term. Capsicum-containing nasal sprays, suspensions, and swabs seem to be safe when applied multiple times over 24 hours or when applied daily or every other day for up to 14 days. Although no serious side effects have been reported in clinical trials, intranasal application of capsicum-containing products can be very painful (14322,14324,14328,14329,14351,14352,14353,14356,14357) (14358,14359,14360,15016,105204). POSSIBLY UNSAFE when used orally, long-term or in high doses. There is concern that long-term use or use of excessive doses might be linked to hepatic or kidney damage, as well as hypertensive crisis (12404,40569,40606). There is insufficient reliable information available about the safety of capsicum when injected.
CHILDREN: POSSIBLY UNSAFE
when used topically in children under 2 years old (272).
There is insufficient reliable information available about the safety of capsicum when used orally in children.
PREGNANCY: LIKELY SAFE
when used topically and appropriately (272).
PREGNANCY: POSSIBLY SAFE
when used orally and appropriately, short-term.
Capsicum 5 mg daily has been used for up to 28 days during the latter half of the second trimester and the third trimester (96457).
LACTATION: LIKELY SAFE
when used topically and appropriately (272).
LACTATION: POSSIBLY UNSAFE
when used orally.
Dermatitis can sometimes occur in infants when foods heavily spiced with capsicum peppers are ingested during lactation (739). Also, observational research suggests that intake of raw capsicum peppers during pregnancy is associated with an increased risk of sensitization to inhalant allergens in children by the age of 2 years (41021).
POSSIBLY SAFE ...when used orally, short-term. A specific supplement (Motilitone, Dong-A ST) containing Corydalis yanhusuo extract in combination with Pharbitis seed extract has been used with apparent safety in a dose of 90 mg daily for up to 4 weeks in clinical research (97158,97159,97160). There is insufficient reliable information available about the safety of Corydalis yanhusuo when used orally as a single ingredient.
CHILDREN: LIKELY UNSAFE
when used orally in newborns.
The berberine constituent of Corydalis yanhusuo can cause kernicterus in newborns, particularly preterm neonates with hyperbilirubinemia (2589).
PREGNANCY: LIKELY UNSAFE
when used orally.
Corydalis yanhusuo might promote menstrual flow and stimulate uterine contractions (12). The berberine constituent of Corydalis yanhusuo 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.
The berberine constituent of Corydalis yanhusuo and other harmful constituents can be transferred to the infant through breast milk (2589).
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.
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.
LIKELY UNSAFE ...when used orally (3,11). Lobelia leaf can be toxic in doses of 600-1000 mg; 4000 mg of the leaf may be fatal (18). There is insufficient reliable information available about the safety of lobelia when used topically.
PREGNANCY AND LACTATION: LIKELY UNSAFE
when used orally due to its emetic effects (4,12).
There is insufficient reliable information available about the safety of lobelia when used topically during pregnancy and lactation.
POSSIBLY SAFE ...when used orally and appropriately, short term. Total glucosides of peony has been used with apparent safety in doses of up to 1800 mg daily for up to 12 months (92786,97949,97950,98466,100992,110432,112861,112862). Peony root extract has been used with apparent safety at a dose of 2250 mg daily for up to 3 months (97216). There is insufficient reliable information available about the safety of peony when used orally, topically, or rectally, long-term.
CHILDREN: POSSIBLY SAFE
when used orally and appropriately, short-term.
Total glucosides of peony has been used with apparent safety in children 1.5-4 years of age at doses up to 180 mg/kg daily or 1.2 grams daily for up to 12 months (92785). Peony root extract 40 mg/kg daily has also been used with apparent safety in children 1-14 years of age for 4 weeks (106851).
PREGNANCY: POSSIBLY UNSAFE
when used orally.
Preliminary research suggests that peony can cause uterine contractions (13400). However, other preliminary research suggests a combination of peony and angelica with or without motherwort, banksias rose, and ligustica, might be safe (11015,48433). Until more is known, avoid use.
LACTATION:
Insufficient reliable information available; avoid using.
LIKELY SAFE ...when used orally in amounts commonly used in foods. Red clover has Generally Recognized As Safe (GRAS) status for use in foods in the US (4912,10372).
POSSIBLY SAFE ...when used orally and appropriately in supplemental amounts. Red clover extracts containing up to 80 mg isoflavones have been used with apparent safety in clinical studies lasting up to 2 years (3375,6127,8925,11089,11091,17091,19540,19556,91524,102901,102840). ...when used topically and appropriately. Red clover extracts have been used topically with apparent safety for up to 4 weeks (102839).
PREGNANCY AND LACTATION: LIKELY SAFE
when used orally in amounts commonly found in foods (4912).
PREGNANCY AND LACTATION: POSSIBLY UNSAFE
when used orally in medicinal amounts.
Red clover has estrogenic activity (19555); avoid using. There is insufficient reliable information available about the safety of the topical use of red clover during pregnancy and lactation.
There is insufficient reliable information available about the safety of Viburnum opulus.
PREGNANCY AND LACTATION:
Insufficient reliable information available; avoid using.
Below is general information about the interactions of the known ingredients contained in the product Flexaherb. Some ingredients may not be listed. This information does NOT represent a recommendation for or a test of this specific product as a whole.
Taking black cohosh with atorvastatin might increase the risk for elevated liver function tests.
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In one case report, a patient taking atorvastatin (Lipitor) developed significantly elevated liver function enzymes after starting black cohosh 100 mg four times daily. Liver enzymes returned to normal when black cohosh was discontinued (16725). It is unclear whether the elevated liver enzymes were due to black cohosh itself or an interaction between atorvastatin and black cohosh.
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Theoretically, black cohosh may reduce the clinical effects of cisplatin.
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Animal research suggests that black cohosh might decrease the cytotoxic effect of cisplatin on breast cancer cells (13101).
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Some research suggests that black cohosh might inhibit CYP2D6, but there is conflicting evidence.
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Some clinical research suggests that black cohosh might modestly inhibit CYP2D6 and increase levels of drugs metabolized by this enzyme (13536). However, contradictory clinical research shows a specific black cohosh product (Remifemin, Enzymatic Therapy) 40 mg twice daily does not significantly inhibit metabolism of a CYP2D6 substrate in healthy study volunteers (16848). Until more is known, use black cohosh cautiously in patients taking drugs metabolized by CYP2D6.
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Theoretically, black cohosh may alter the effects of estrogen therapy.
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Theoretically, taking black cohosh with hepatotoxic drugs may increase the risk of liver damage.
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Black cohosh may inhibit one form of OATP, OATP2B1, which could reduce the bioavailability and clinical effects of OATP2B1 substrates.
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In vitro research shows that black cohosh modestly inhibits OATP2B1 (35450). 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.
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Theoretically, using topical capsaicin may increase the risk of ACE inhibitor-induced cough.
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There is one case report of a topically applied capsaicin cream contributing to the cough reflex in a patient using an ACEI (12414). However, it is unclear if this interaction is clinically significant.
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Theoretically, capsicum may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.
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In vitro research shows that capsicum might increase the effects of antiplatelet drugs (12406,12407). Also, population research shows that capsicum is associated with an increased risk of self-reported bleeding in patients taking warfarin (12405,20348). However, clinical research shows that taking a single dose of capsaicin (Asian Herbex Ltd.), the active ingredient in capsicum, 400-800 mcg orally in combination with aspirin 500 mg does not decrease platelet aggregation when compared with taking aspirin 500 mg alone. Also, there was no notable effect on measures of platelet aggregation with capsaicin (92990). It is unclear whether capsaicin must be used in more than a single dose to affect platelet aggregation.
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Theoretically, taking capsicum with antidiabetes drugs might increase the risk of hypoglycemia.
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Preliminary clinical research shows that consuming capsicum 5 grams along with a glucose drink attenuates the rise in plasma glucose after 30 minutes by 21%, decreases the 2-hour postprandial area under the curve of plasma glucose by 11%, and increases the 2-hour postprandial area under the curve of plasma insulin by 58% in healthy individuals when compared with placebo (40453,40614). Other clinical research shows that taking capsicum 5 mg daily for 28 days significantly reduces postprandial blood glucose and insulin levels, but not fasting blood glucose and insulin levels, in patients with gestational diabetes (96457).
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Theoretically, taking capsicum with aspirin might reduce the bioavailability of aspirin.
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Animal research shows that acute or chronic intake of capsicum pepper reduces oral aspirin bioavailability (22617). This has not been shown in humans.
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Theoretically, taking capsicum with ciprofloxacin might increase levels and adverse effects of ciprofloxacin.
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Animal research shows that concomitant use of capsaicin, the active constituent of capsicum, and ciprofloxacin increases the bioavailability of ciprofloxacin by up to 70% (22613).
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Theoretically, taking capsicum with theophylline might increase the levels and adverse effects of theophylline.
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Theoretically, Corydalis yanhusuo might increase the risk of bleeding when used with anticoagulant or antiplatelet drugs.
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Theoretically, Corydalis yanhusuo may increase the risk of hypoglycemia when taken with antidiabetes drugs.
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Theoretically, Corydalis yanhusuo might have additive effects with antihypertensive drugs.
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Corydalis yanhusuo contains berberine. Animal research suggests that berberine can have hypotensive effects (33692,34308). Also, a clinical study suggests that taking berberine in combination with amlodipine can lower systolic and diastolic blood pressure when compared with amlodipine alone (91956). Theoretically, Corydalis yanhusuo might also reduce blood pressure.
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Theoretically, Corydalis yanhusuo might increase the sedative effects of CNS depressants.
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Theoretically, Corydalis yanhusuo might increase blood levels of cyclosporine.
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Corydalis yanhusuo contains berberine. Preliminary clinical research shows that berberine can reduce metabolism of cyclosporine and increase serum levels, likely through inhibition of cytochrome P450 3A4 (CYP3A4), which metabolizes cyclosporine (13524). Theoretically, Corydalis yanhusuo might also reduce the metabolism of cyclosporine.
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Theoretically, Corydalis yanhusuo might increase serum levels of drugs metabolized by CYP2C9.
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Corydalis yanhusuo contains berberine. Preliminary clinical research shows that berberine can inhibit CYP2C9 (34279). Theoretically, Corydalis yanhusuo might also inhibit CYP2C9.
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Theoretically, Corydalis yanhusuo might increase serum levels of drugs metabolized by CYP2D6.
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Theoretically, Corydalis yanhusuo might increase serum levels of drugs metabolized by CYP3A4.
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Theoretically, Corydalis yanhusuo may increase serum levels of dextromethorphan.
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Corydalis yanhusuo contains berberine. Preliminary clinical research shows that berberine can inhibit cytochrome P450 2D6 (CYP2D6) activity and reduce the metabolism of dextromethorphan (34279). Theoretically, Corydalis yanhusuo may also inhibit the metabolism of dextromethorphan.
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Theoretically, Corydalis yanhusuo might reduce the therapeutic effects of losartan by decreasing its conversion to its active form.
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Corydalis yanhusuo contains berberine. Preliminary clinical research suggests that berberine can inhibit cytochrome P450 2C9 (CYP2C9) activity and reduce metabolism of losartan (34279). Theoretically, Corydalis yanhusuo might also inhibit the metabolism of losartan.
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Theoretically, Corydalis yanhusuo might increase the therapeutic and adverse effects of metformin.
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Corydalis yanhusuo contains berberine. In vitro and animal studies show that berberine can increase the systemic exposure and half-life of metformin, potentially increasing metformin's effects and side effects. This interaction seems to be most apparent when berberine is administered 2 hours prior to metformin. Taking berberine and metformin at the same time does not appear to increase systemic exposure to metformin (103195). It is unclear if Corydalis yanhusuo might have this same effect.
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Theoretically, Corydalis yanhusuo might reduce metabolism of midazolam, which might increase the risk of severe adverse effects.
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Corydalis yanhusuo contains berberine. Preliminary clinical research shows that berberine can inhibit cytochrome P450 3A4 (CYP3A4) activity and reduce metabolism of midazolam (34279). Theoretically, Corydalis yanhusuo might also inhibit the metabolism of midazolam.
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Theoretically, Corydalis yanhusuo might increase the sedative effect of pentobarbital.
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Corydalis yanhusuo contains berberine. Animal research shows that berberine can prolong pentobarbital-induced sleeping time (13519). Theoretically, Corydalis yanhusuo might increase the sedative effects of pentobarbital.
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Theoretically, Corydalis yanhusuo might increase blood levels of tacrolimus.
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Corydalis yanhusuo contains berberine. In a 16-year-old patient with idiopathic nephrotic syndrome who was being treated with tacrolimus 6.5 mg twice daily, intake of berberine 200 mg three times daily increased the blood concentration of tacrolimus from 8 to 22 ng/mL. Following a reduction of the tacrolimus dose to 3 mg daily, blood levels of tacrolimus decreased to 12 ng/mL (91954). It is unclear if Corydalis yanhusuo might have this same effect.
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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, licorice might reduce the effects of antihypertensive drugs.
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Theoretically, licorice might reduce the effects of cisplatin.
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In animal research, licorice diminished the therapeutic efficacy of cisplatin (59763).
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Theoretically, concomitant use of licorice and corticosteroids might increase the side effects of corticosteroids.
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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).
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Theoretically, licorice might decrease the levels and clinical effects of CYP1A2 substrates.
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In vitro research shows that licorice induces CYP1A2 enzymes (111404).
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Theoretically, licorice might increase levels of drugs metabolized by CYP2B6.
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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.
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Theoretically, licorice might increase levels of drugs metabolized by CYP2C19.
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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.
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Theoretically, licorice might increase levels of drugs metabolized by CYP2C8.
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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.
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Theoretically, licorice might increase or decrease levels of drugs metabolized by CYP2C9.
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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.
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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.
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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).
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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).
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Theoretically, licorice might increase or decrease the effects of estrogen therapy.
Details
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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).
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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.
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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.
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Theoretically, licorice might decrease the absorption of P-glycoprotein substrates.
Details
In vitro research shows that licorice can increase P-glycoprotein activity (104561).
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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).
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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.
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Lobelia is thought to have diuretic properties. Theoretically, due to these potential diuretic effects, lobelia might reduce excretion and increase levels of lithium. The dose of lithium might need to be decreased.
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Theoretically, combining peony with anticoagulant or antiplatelet drugs might increase the risk of bleeding.
Details
In vitro research suggests that peony might have antiplatelet, anticoagulant, and antithrombotic effects (92787).
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Theoretically, peony might increase the levels and clinical effects of clozapine.
Details
In vitro research shows that peony suppresses the metabolism of clozapine via weak-to-moderate inhibitory effects on cytochromes P450 (CYP) 1A2 and CYP3A4 (92790). This effect has not been reported in humans.
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Theoretically, peony might interfere with contraceptive drugs due to competition for estrogen receptors.
Details
In vitro and animal research shows that peony extract has estrogenic activity (100990). Concomitant use might also increase the risk for estrogen-related adverse effects.
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Theoretically, use of peony may increase the levels and clinical effects of drugs metabolized by CYP1A2.
Details
In vitro research shows that peony suppresses the metabolism of clozapine via weak-to-moderate inhibitory effects on CYP1A2 and CYP3A4 (92790). This effect has not been reported in humans.
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Theoretically, use of peony may increase the levels and clinical effects of drugs metabolized by CYP3A4.
Details
In vitro research shows that peony suppresses the metabolism of clozapine via weak-to-moderate inhibitory effects on CYP1A2 and CYP3A4 (92790). This effect has not been reported in humans.
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Theoretically, concomitant use of large amounts of peony might interfere with hormone replacement therapy and/or increase the risk for estrogen-related adverse effects.
Details
In vitro and animal research shows that peony extract has estrogenic activity (100990). Theoretically, peony might compete for estrogen receptors and/or cause additive estrogenic effects.
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Theoretically, peony might reduce the levels and clinical effects of phenytoin.
Details
Animal research shows that taking peony root reduces levels of phenytoin (8657). Some researchers suggest that peony root might affect cytochrome P450 (CYP) 2C9, which metabolizes phenytoin. However, preliminary research in humans shows that peony root does not alter levels of losartan (Cozaar), which is also metabolized by CYP2C9 (11480).
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Although some laboratory research suggests that red clover may have anticoagulant and antiplatelet activity, clinical research has not shown this effect.
Details
In vitro research suggests that genistein in red clover has antiplatelet effects, and historically, red clover was thought to have anticoagulant effects due to its coumarin content. However, some experts state that this is unlikely as most natural coumarins have not been shown to have anticoagulant effects, and their content in red clover is low (17091,19557,19558,19559). Additionally, some clinical research in postmenopausal patients found no effect on coagulation or prothrombin time with the use of red clover flowering tops 378 mg daily for 12 months or red clover isoflavone (Rimostil) 50 mg daily for 2 years (17091,91524).
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Theoretically, soy might reduce the clearance of caffeine; however, a small clinical study found no effect.
Details
Red clover contains genistein. Taking genistein 1 gram daily for 14 days seems to inhibit caffeine clearance and metabolism in healthy females (23582). However, this effect does not seem to occur with the lower amounts of genistein found in red clover. A clinical study in healthy postmenopausal individuals shows that taking red clover capsules standardized to contain 60 mg isoflavones twice daily for 14 days does not affect the pharmacokinetics of caffeine (105693).
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Theoretically, red clover might increase levels of drugs metabolized by CYP1A2; however, a small clinical study found no effect.
Details
In vitro evidence shows that red clover inhibits CYP1A2 (12479). However, a clinical study in healthy postmenopausal individuals shows that taking red clover capsules standardized to contain 60 mg isoflavones twice daily for 14 days does not affect the pharmacokinetics of caffeine, a CYP1A2 probe substrate (105693).
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Theoretically, red clover might increase the levels and clinical effects of drugs metabolized by CYP2C19.
Details
In vitro evidence suggests that red clover weakly inhibits CYP2C19 (12479). This interaction has not been reported in humans.
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Theoretically, red clover might increase levels of drugs metabolized by CYP2C9; however, a small clinical study found no effect.
Details
In vitro evidence suggests that red clover might inhibit CYP2C9 (12479). However, a clinical study in healthy postmenopausal individuals shows that taking red clover capsules standardized to contain 60 mg isoflavones twice daily for 14 days does not affect the pharmacokinetics of tolbutamide, a CYP2C9 probe substrate (105693).
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Theoretically, red clover might increase levels of drugs metabolized by CYP3A4; however, a small clinical study found no effect.
Details
In vitro evidence shows that red clover might inhibit CYP3A4 isoenzymes (6450,12479). However, a clinical study in healthy postmenopausal individuals shows that taking red clover capsules standardized to contain 60 mg isoflavones twice daily for 14 days does not affect the pharmacokinetics of alprazolam, a CYP3A4 probe substrate (105693).
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Theoretically, concomitant use of large amounts of red clover might interfere with estrogen therapy.
Details
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Theoretically, red clover might increase the risk of methotrexate toxicity.
Details
In a case report, a 52-year-old female receiving weekly methotrexate injections for psoriasis developed symptoms of methotrexate toxicity, including severe vomiting and epigastric pain, after three days of taking red clover 430 mg daily. Toxicity resolved after red clover was discontinued. However, no liver function tests or methotrexate levels were reported (91522).
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Theoretically, the phytoestrogens in red clover might interfere with tamoxifen.
Details
In vitro and animal research suggests that genistein, a constituent of red clover, might antagonize the antitumor effects of tamoxifen (8192). However, there is some evidence from an animal study that red clover does not reduce the efficacy of tamoxifen (102901). Until more is known, tell patients taking tamoxifen to avoid red clover.
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Below is general information about the adverse effects of the known ingredients contained in the product Flexaherb. 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, black cohosh is generally well tolerated when used in typical doses.
Most Common Adverse Effects:
Orally: Breast tenderness, dizziness, gastrointestinal upset, headache, irritability, rash, tiredness.
Serious Adverse Effects (Rare):
Orally: Endometrial hyperplasia and hepatotoxicity, although data are conflicting for both.
Cardiovascular
...A single case of reversible bradycardia has been reported for a 59-year-old female who took one tablet of a specific black cohosh product (Remifemin, Schaper & Brümmer) daily for 2 weeks.
The adverse event was considered probably related to black cohosh use, although the exact mechanism by which black cohosh exerted this effect was unclear (35920).
There has been concern that, if black cohosh has estrogen-like effects, it could also potentially cause estrogen-like side effects including increased risk for thromboembolism and cardiovascular disease. These outcomes have not been specifically assessed in long-term trials; however, some research shows that a specific black cohosh extract (CimiPure, PureWorld) does not significantly affect surrogate markers for thromboembolism and cardiovascular risk such as fibrinogen, cholesterol, triglycerides, glucose, or insulin levels compared to placebo (16850).
Dermatologic ...Black cohosh has been associated with skin irritation and rashes (7054,10987,14330,15889,35853). A case report describes a patient who developed cutaneous pseudolymphoma 6 months after starting a specific black cohosh extract (Remifemin). Symptoms resolved within 12 weeks of discontinuing black cohosh (15890).
Gastrointestinal ...Orally, black cohosh can commonly cause gastrointestinal upset (4383,4615,4616,10988,13184,35824,35853,35965,103269,111714). Constipation and indigestion have also been reported (7054,35852).
Genitourinary
...Orally, black cohosh, including the specific black cohosh product Remifemin, may cause vaginal bleeding and breast tenderness in some postmenopausal patients (15889,35824).
However, the frequency of these events seems to be less than that of tibolone, a prescription hormone medication used to treat symptoms of menopause (15889,35904).
Due to the potential estrogen-like effects, there is concern that black cohosh might increase the risk of endometrial hyperplasia. However, a specific black cohosh extract CR BNO 1055 (Klimadynon/Menofem, Bionorica AG) does not appear to cause endometrial hyperplasia. Clinical research in postmenopausal adults shows that taking 40 mg daily of this extract for 12 weeks does not significantly increase superficial cells when compared with placebo, and causes significantly fewer superficial cells when compared with conjugated estrogens (Premarin) (14330). Additional clinical research shows that taking 40 mg daily of this extract for a year does not increase the risk of endometrial hyperplasia or endometrial thickening in postmenopausal adults (15036). Another specific combination product containing black cohosh extract plus St. John's wort (Gynoplus, Jin-Yang Pharm) also does not significantly increase superficial cells compared to placebo after 12 weeks of treatment (15893). Some patients taking tamoxifen plus black cohosh have experienced endometrial hyperplasia and vaginal bleeding. However, these effects are more likely due to tamoxifen than black cohosh (7054).
Hepatic
...There is concern that black cohosh might cause liver disease, hepatotoxicity, or hepatitis.
Adverse effects on the liver have not been documented in clinical studies. However, multiple case reports of liver toxicity, hepatitis, and abnormal liver function have been described in females taking black cohosh products alone or in combination with other herbs or drugs. In some cases, patients developed liver failure and required immediate liver transplantation (4383,10692,11909,12006,13144,14469,15160,16721,16722,16723) (16724,16727,35883,35888,35890,35895,89465,101592,107906). In one case, a female developed autoimmune hepatitis after 3 weeks of taking black cohosh. Symptoms resolved 2 weeks after discontinuing black cohosh (11906). In at least three cases, females have developed elevated liver enzymes and symptoms of hepatotoxicity after taking black cohosh products. Symptoms resolved and liver enzymes normalized within a week of discontinuing black cohosh (16725,16726). Analysis of two liver biopsies suggests that hepatotoxicity associated with black cohosh use results from the accumulation of 4HNE protein adducts in the cytoplasm of liver cells, which promotes the migration of lymphocytes to the affected area and induces an autoimmune response leading to troxis necrosis (89469).
However, many of these cases are poorly documented. Causality is possible based on some reports; however, other reports do not indicate that black cohosh is the probable cause of the events (15891,15892,16722,16723,16727,89465). Hepatitis can occur with no identifiable cause, raising the possibility that black cohosh and hepatitis might have been coincidental in some cases. Also, plant misidentification can occur, resulting in accidental substitution of a hepatotoxic plant (11910). Therefore, some experts argue that these cases do not provide conclusive evidence that black cohosh is responsible for liver disease (17085,35882,111634). Nonetheless, some countries require cautionary labeling on black cohosh products suggesting a risk of liver toxicity. The United States Pharmacopeia also recommends cautionary labeling on black cohosh products (16722). Until more is known about this potential risk, consider monitoring liver function in patients who take black cohosh.
Musculoskeletal
...One patient treated with black cohosh in a clinical trial discontinued treatment due to edema and arthralgia (35897).
Black cohosh has been linked to asthenia and muscle damage in one case. A 54-year-old female experienced asthenia with elevated creatinine phosphokinase (CPK) and lactate dehydrogenase (LDH) levels while taking black cohosh. The patient had taken a specific black cohosh extract (Remifemin) for 1 year, discontinued it for 2 months, restarted it, and then experienced symptoms 2 months later. Symptoms began to resolve 10 days after discontinuing black cohosh (14299).
Neurologic/CNS
...Orally, black cohosh may cause headache, dizziness, or tiredness (35852,35886).
There is one case report of seizures in a female who used black cohosh, evening primrose oil, and chasteberry (10988).
Also, there has been a case report of severe complications, including seizures, renal failure, and respiratory distress, in an infant whose mother was given an unknown dose of black cohosh and blue cohosh at 42 weeks gestation to induce labor (1122,9492,9493). However, this adverse effect may have been attributable to blue cohosh.
In another case report, orobuccolingual dyskinesia, including tongue-biting, eating difficulties, and speech problems, was reported in a 46-year-old female who took two tablets containing black cohosh 20 mg and Panax ginseng 50 mg daily for 15 months. The patient's condition improved after stopping treatment with the herbs and taking clonazepam 2 mg daily with baclofen 40 mg daily (89735).
Ocular/Otic ...There is some concern that black cohosh might increase the risk of retinal vein thrombosis due to its estrogenic activity. In one case, a patient with protein S deficiency and systemic lupus erythematosus (SLE) experienced retinal vein thrombosis 3 days after taking a combination product containing black cohosh 250 mg, red clover 250 mg, dong quai 100 mg, and wild yam 276 mg (13155). It is unclear if this event was due to black cohosh, other ingredients, the combination, or another factor.
Oncologic ...There is some concern that black cohosh may affect hormone-sensitive cancers, such as some types of breast or uterine cancer, due to its potential estrogenic effects. However, evidence from a cohort study suggests that regular use of black cohosh is not associated with the risk of breast or endometrial cancer (17412,111634).
Psychiatric ...A 36-year-old female with a 15-year history of depression developed mania with psychotic and mixed features after taking a black cohosh extract 40 mg daily. The patient gradually recovered after stopping black cohosh and receiving treatment with antipsychotics (104517).
Pulmonary/Respiratory ...There has been a case report of severe complications, including seizures, renal failure, and respiratory distress, in an infant whose mother was given an unknown dose of black cohosh and blue cohosh at 42 weeks gestation to induce labor (1122,9492,9493). However, this adverse effect may have been attributable to blue cohosh.
Renal ...There has been a case report of severe complications, including seizures, renal failure, and respiratory distress, in an infant whose mother was given an unknown dose of black cohosh and blue cohosh at 42 weeks gestation to induce labor (1122,9492,9493). However, this adverse effect may have been attributable to blue cohosh.
Other ...While rare, weight gain has been reported in some patients taking black cohosh. However, in most cases the causality could not be established. A review of the literature, including published case reports, spontaneous reports to adverse event databases, and clinical trials, suggests that black cohosh does not cause weight gain (107907).
General
...Orally, capsicum is generally well tolerated in amounts typically found in food or when the extract is used in doses of up to 200 mg daily.
Topically and intranasally, capsaicin, a constituent of capsicum, is generally well tolerated.
Most Common Adverse Effects:
Orally: Belching, bloating, burning, diarrhea, dyspepsia, gas, headache, mild constipation, nausea, rhinorrhea, skin flushing, and sweating.
Serious Adverse Effects (Rare):
Orally: Cases of myocardial infarction and hypertensive crisis have been reported.
Cardiovascular
...Orally, palpitation was reported in one clinical trial (105196).
One case of myocardial infarction has been reported in a 41-year-old male without cardiovascular risk factors; the event was attributed to the use of an oral capsicum pepper pill that the patient had been taking for weight loss (40768). Another case of coronary vasospasm and acute myocardial infarction has been reported for a healthy 29-year-old male; the event was attributed to the use of a topical capsicum-containing patch that the patient had been applying to the middle of the back for 6 days (40658). Two cases of arterial hypertensive crisis have been reported for individuals who ingested a large amount of peppers and chili peppers the day before. One of the patients also had an acute myocardial infarction, and the other had high levels of thyroid stimulating hormone (40569,40606).
Dermatologic
...Orally, capsicum or its constituent capsaicin may cause urticaria and skin wheals in rare cases (96457,105203).
Topically, capsicum can cause a prickling sensation, itching, pain, burning, edema, stinging, irritation, rash, and erythema. About 1 in 10 patients who use capsaicin topically discontinue treatment because of adverse effects. These effects seem to occur more often with topical formulations containing higher concentrations of capsaicin, the active constituent of capsicum. Side effects tend to diminish with continued use (12401,15260,15261,40358,40439,40483,40547,40676,40682,40719)(40784,40847,92979,92983,92984,96453,105193,105197,105202,111514). In one case, application of a capsaicin 8% patch (Qutenza) for 60 minutes caused a second-degree burn, characterized by burning, erythema, severe pain, and blistering at the administration site. The burn was treated with topical corticosteroids, but 9 months later neuropathic pain persisted, resulting in limited mobility. It is unclear whether the mobility sequalae were caused by topical capsaicin or the patient's pre-existing neurological disorders (111514). Skin contact with fresh capsicum fruit can also cause irritation or contact dermatitis (12408).
Intranasally, capsaicin can cause nasal burning and pain in most patients. It also often causes lacrimation, sneezing, and excessive nasal secretion; however, these side effects appear to diminish with repeat applications (14323,14329,14358). In some cases, the burning sensation disappears after 5-8 applications (14351,14358). In some cases, patients are pretreated with intranasal lidocaine to decrease the pain of intranasal capsaicin treatment. However, even with lidocaine pretreatment, patients seem to experience significant pain (14324).
Gastrointestinal
...Orally, capsicum can cause upper abdominal discomfort, including irritation, fullness, dyspepsia, gas, bloating, nausea, epigastric pain and burning, anal burning, diarrhea, mild constipation, and belching (12403,12410,40338,40427,40456,40503,40560,40584,40605,40665)(40718,40725,40745,40808,40828,96456,96457,105194,105196).
There is a case report of a 3-year-old female who experienced a burning and swollen mouth and lips after touching the arm of a parent that had been treated with a capsaicin patch and then placing the fingers in the mouth (105199). Excessive amounts of capsaicin can lead to gastroenteritis and hepatic necrosis (12404). In a case report, a 40-year-old male with diabetes consumed white wine daily and chewed cayenne which was thought to result in black teeth stains and loss of enamel (40809). Some preliminary research links ingestion of capsaicin with stomach and gallbladder cancer; however the link may be due to contamination of capsaicin products with carcinogens (40771).
Topically, capsaicin can cause diarrhea and vomiting (105202).
Immunologic ...In a case report, a 34-year-old female had anaphylaxis involving difficulty breathing and stupor and also urticaria after consuming a red bell pepper, which is in the capsicum genus. The causal chemical was theorized to be 1,3-beta-glucanase (92978). In another case report, a 33-year-old female experienced angioedema, difficulty breathing and swallowing, and urticaria after ingesting raw green and red peppers (92982).
Neurologic/CNS ...Orally, capsicum can cause sweating and flushing of the head and neck, lacrimation, headache, faintness, and rhinorrhea (7005,12410,105196,105203). Topically, applying capsaicin can cause headache (96450,105202). Injection of capsaicin into the intermetatarsal space has also been associated with headache (96454).
Ocular/Otic
...Topically, capsicum can be extremely irritating to the eyes and mucous membranes.
Capsicum oleoresin, an oily extract in pepper self-defense sprays, causes intense eye pain. It can also cause erythema, blepharospasm, tearing, shortness of breath, and blurred vision. In rare cases, corneal abrasions have occurred (12408,12409,40345,40348,40383,40720,40857).
Inhalation of capsicum can cause eye irritation, and allergic alveolitis (5885). In a case report, a 38-year-old female had acute anterior uveitis that developed about 12 hours after using a specific patch (Isola Capsicum N Plus) that contained capsaicin 1.5 mg per patch and methyl salicylate 132 mg per patch for neck pain. The uveitis was controlled with topical steroids and did not recur (92977).
Oncologic ...Population research suggests that moderate to high intake of capsaicin, the active constituent of capsicum, is associated with an increased risk of gastric cancer, while low intake is associated with a decreased risk. It is not clear from the study what amount of capsaicin is considered high versus low intake (92988). Additionally, some research suggests that any link may be due to contamination of capsaicin products with carcinogens (40771).
Pulmonary/Respiratory
...Orally, difficulty breathing was reported in a clinical trial (105196).
Topically, nasopharyngitis related to the use of a cream containing capsaicin has been reported (105202).
Inhalation of capsicum and exposure to capsicum oleoresin spray can cause cough, dyspnea, pain in the nasal passages, sneezing, rhinitis, and nasal congestion (5885,15016,40522,40546,40647). In rare cases, inhalation of the capsicum oleoresin or pepper spray has caused cyanosis, apnea, respiratory arrest and death in people. Death was caused by asphyxiation probably due to acute laryngeal edema and bronchoconstriction from inhalation of the capsicum oleoresin spray (40546,40672,40837,40879).
In a case report, a 47-year-old female who was exposed to capsaicin gas for more than 20 minutes experienced acute cough, shortness of breath, short-term chest pain, wheezing, and difficulty breathing for months afterwards (92980). In rare cases, exposure to capsicum oleoresin spray resulted in apnea, pulmonary injury, cyanosis, and even respiratory arrest (40383,40546).
General
...Orally, Corydalis yanhusuo is generally well tolerated.
Serious Adverse Effects (Rare):
Orally: Clonic spasms and muscle tremors with high doses.
Musculoskeletal ...Orally, clonic spasms and muscle tremors may occur with overdoses of Corydalis yanhusuo (18).
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
...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).
General ...Orally, lobelia can cause nausea, vomiting, diarrhea, coughing, dizziness, tremors, and throat irritation. These adverse effects have been reported with doses as low as 50 mg (4,16414). Lobelia leaf can cause toxicity when taken in doses of 600 mg or higher. Symptoms of lobelia toxicity include sweating, tachycardia, convulsions, hypothermia, hypotension, coma, and death (4,11).
Cardiovascular ...Orally, high doses of lobelia leaf can cause toxicity. Symptoms of lobelia toxicity include tachycardia, hypotension, and death (4,11).
Gastrointestinal ...Orally, lobelia can cause nausea, vomiting, diarrhea, and throat irritation (4,16414).
Neurologic/CNS ...Orally, lobelia can cause dizziness and tremors. High doses of lobelia leaf can cause toxicity. Symptoms of lobelia toxicity include convulsions, coma, and death (4,11).
Pulmonary/Respiratory ...Orally, lobelia can cause coughing and throat irritation (4,16414).
Other ...Orally, high doses of lobelia leaf can cause toxicity resulting in death. Toxicity has been reported to occur at doses as low as 600 mg, with doses of 4000 mg or more considered to be fatal (4,11).
General
...Orally, peony seems to be well tolerated when used alone and as part of Chinese herbal formulas.
Most Common Adverse Effects:
Orally: Abdominal distension, anorexia, diarrhea, gastrointestinal discomfort, nausea.
Topically: Dermatitis.
Dermatologic ...Topically, peony has been reported to cause contact dermatitis (13555).
Endocrine ...Orally, a specific traditional Chinese medicine preparation called DDT has been reported to lower follicle-stimulating hormone (FSH) levels and increase estradiol levels. It is not known if this effect is due to peony or the other ingredients (48404). Another specific traditional Chinese medicine preparation, Toki-shakuyaku-san, has been reported to increase plasma progesterone levels in some patients. It is not known if this effect is due to peony or the other ingredients (15294).
Gastrointestinal ...Orally, peony and total glucosides of peony (TGP) have been reported to cause gastrointestinal discomfort, including abdominal distension, anorexia, diarrhea, and nausea, in some patients (13538,92785,97949,98466,100992). In one clinical study, diarrhea was reported in 5% of patients taking TGP 600 mg three times daily for 24 weeks versus 1% of patients taking placebo (100992).
Hematologic ...Orally, there is one case report of easy gum bleeding, epistaxis, and skin bruising with an international normalized ratio (INR) above 6 in a 61-year-old male who was previously stable on warfarin therapy. This patient had switched from one brand of quilinggao, a popular Chinese herbal product, to another brand 5 days prior. This product contained Fritillaria spp. (beimu), Paeonia rubra, Chinese peony (chishao), Lonicera japonica (jinyinhua), and Poncirus trifoliata (jishi). The patient's INR decreased to 1.9 after temporary withdrawal of warfarin therapy. Upon re-initiation of quilinggao, his INR increased to 5.2. It is not known if the increased INR is due to peony or the other ingredients (68343).
General
...Orally and topically, red clover seems to be well tolerated.
Most Common Adverse Effects:
Orally: Myalgia, nausea, and vaginal spotting.
Dermatologic ...Orally, a specific red clover isoflavone product (Promensil) has been associated with mild cases of psoriasis and thrush, although a direct causal link has not been established (9552).
Gastrointestinal ...Orally, red clover has been reported to cause nausea (8194).
Genitourinary ...In human research, 80 mg, but not 40 mg, of a specific red clover isoflavone product (Promensil) increased the duration of menstrual cycles in patients with mastalgia (9552). Red clover has also been reported to cause vaginal spotting (8194).
Hematologic ...In one case report, a 53-year-old female had a spontaneous subarachnoid hemorrhage associated with the use of an herbal supplement containing red clover, dong quai, and eleuthero. It is not clear if this was due to red clover, another ingredient, the combination of ingredients, or other factors (70419). In another case report, a 55-year-old female with protein S deficiency and systemic lupus erythematosus (SLE) had temporary vision loss in the left eye from hemiretinal vein thrombosis 3 days after taking a combination phytoestrogen product containing red clover 250 mg, wild yam 276 mg, dong quai 100 mg, and black cohosh 250 mg (13155). It is unclear if red clover contributed to this event.
Musculoskeletal ...Orally, red clover has been reported to cause myalgia (8194).
Neurologic/CNS ...Orally, a specific red clover isoflavone product (Medoflavon) has been associated with headache, although with a similar frequency to placebo (19545).
Oncologic ...Due to potential estrogenic effects of red clover isoflavones, there has been some concern that red clover might increase the risk of estrogen-sensitive cancers such as breast cancer or uterine cancer. A meta-analysis of 8 clinical trials suggests that increased intake of red clover- and soy-derived isoflavones may modestly increase mammographic breast density in premenopausal, but not postmenopausal, adults when compared with placebo. However, in a sub-group analysis assessing only isolated red clover isoflavones, there was no change in breast density (70428). Furthermore, a 2015 review by the European Food Safety Authority (EFSA) reported no increase in risk of breast cancer in females taking isoflavone-containing supplements (91725). Similarly, no effect was found on endometrial thickness and histopathological changes in the uterus after up to 36 months of supplementation with 40-120 mg daily of isoflavones from red clover extract (91725).
General ...No adverse effects have been reported; however, a thorough evaluation of safety outcomes has not been conducted.
