Goldenseal, an endangered plant, is related to the buttercup. Its active components are beta-hydrastine, canadine, canadaline, and berberine, which have antiseptic activity. Berberine is also active against diarrhea. It is available in liquid, tablet, and capsule forms.
(See also Overview of Dietary Supplements.)
Claims for Goldenseal
Because berberine is claimed to lower blood sugar, some people take goldenseal to regulate their blood sugar levels.
Evidence for Goldenseal
The effectiveness of goldenseal as a cold remedy has not been proved. In some relatively well-designed studies, berberine isolated from goldenseal reduced diarrhea, including diarrhea in people with irritable bowel syndrome.
Emerging evidence shows that in people with diabetes, berberine can decrease fasting and postprandial glucose and hemoglobin A1C (HbA1C).
Berberine has also been shown to lower cholesterol, blood pressure, and body weight.
Side Effects of Goldenseal
Goldenseal can cause many side effects, including digestive irritation and upset, anxiety, contractions of the uterus, and jaundice in newborns. If taken in large amounts, goldenseal can cause seizures and respiratory failure and may affect contraction of the heart.
Women who are pregnant or breastfeeding, newborns, and people who have a seizure disorder or problems with blood clotting should not take goldenseal.
Berberine may damage DNA in some cells. What effect this has in people is not yet known.
Drug Interactions with Goldenseal
metformin. The berberine in goldenseal may increase the hypoglycemic effects of antihyperglycemic medications.
Recommendations for Goldenseal
Goldenseal may cause many serious side effects and drug interactions, and the health benefits of goldenseal, if any, are likely small and generally achievable with the use of other medications; therefore, goldenseal is not recommended. Pregnant or breastfeeding women should be advised not to take goldenseal.
More Information
The following English-language resource may be useful. Please note that THE MANUAL is not responsible for the content of this resource.
National Institutes of Health's National Center for Complementary and Integrative Health: Goldenseal
