The Disadvantages of Black Cohosh

Black cohosh, a popular medicinal herb, has been used for centuries as a naturopathic remedy for hot flashes, low libido, amenorrhea and other common female ailments. The National Center for Complementary and Alternative Medicine (NCCAM) notes that studies indicate that black cohosh is relatively safe when it is taken for six months or less, but the organization warns that few studies have evaluated its long-term safety. Furthermore, some studies have produced discouraging results regarding black cohosh's efficacy as a medicine. Like all medicinal herbs, black cohosh is associated with some risks and disadvantages.

Unverified Potency

• The U.S. Food and Drug Administration does not strictly control the production of herbal supplements. Some manufacturers take advantage of this legal loophole and sell black cohosh formulas that are impure or counterfeit. Anyone interested in taking black cohosh should seek a brand that offers guaranteed-potency supplements that have been verified through a third-party agency.

Mixed Evidence

• The National Institutes of Health Office of Dietary Supplements states that, while some clinical trials support black cohosh's efficacy as a treatment for menopausal symptoms, other studies suggest that it is ineffective. Most clinical trials involving black cohosh have been poorly designed, so scientists find it difficult to fully establish whether or not the herb is effective.

Side Effects

• The National Institutes of Health note that side effects from black cohosh are relatively mild and uncommon. The most common complaints among women taking black cohosh are headaches and abdominal pain.

Possible Liver Damage

• There is no clear evidence to support the notion that black cohosh can harm the liver. However, according to the National Institutes of Health, one 47-year-old woman experienced acute hepatitis while taking black cohosh supplements. While doctors were unable to conclude that black cohosh was responsible for the woman's condition, practitioners generally recommend that people with pre-existing liver disease avoid it. Stop taking black cohosh and notify your doctor if you experience symptoms of liver disease, such as dark urine or yellowing of the skin and eyes.