Black Cohosh

Background

• Black cohosh, a member of the buttercup family, grows in North America. Native Americans used black cohosh for treatment of a variety of conditions including kidney ailments, malaria, sore throat, and menstrual cramps. It has also been used medicinally in Germany since the late 19th century.
• Currently, black cohosh is promoted as a dietary supplement for menopause symptoms. It has also been promoted for other conditions, including menstrual cramps and premenstrual syndrome, and to induce labor.
• The part of the black cohosh plant used in herbal preparations is the root or rhizome (underground stem).

How Much Do We Know?

• A substantial number of studies in people have evaluated black cohosh for menopause symptoms. Much less research has been done on black cohosh for other conditions.

What Have We Learned?

• A 2023 review of 22 studies of products containing black cohosh extracts, alone or in combination with other herbs, found that they were potentially beneficial for overall menopause symptoms. Data on specific symptoms showed improvements in hot flashes but not anxiety or depressive symptoms.
• It’s uncertain whether black cohosh can reduce hot flashes related to breast cancer treatment.
• There aren’t enough reliable data to show whether black cohosh is effective for other uses.

What Do We Know About Safety?

• While black cohosh has been used safely in research studies that lasted as long as a year and is generally well tolerated, concerns have been raised that it may cause liver damage in some people.
  • Cases of liver damage—some very serious—have been reported in people taking products labeled as black cohosh. These problems are rare, and it’s uncertain whether black cohosh was responsible for them. If you take black cohosh, consult your health care provider if you develop symptoms of liver damage such as dark urine and fatigue.
• Some commercial black cohosh products have been found to contain the wrong herb or to contain mixtures of black cohosh and other herbs that are not listed on the label. It is possible but not proven that these contaminants might be responsible for cases of liver damage linked to black cohosh products.
• Black cohosh and blue cohosh (Caulophyllum thalictroides) are different herbs. Blue cohosh may cause adverse effects such as high blood pressure, high blood sugar, and chest pain. The use of blue cohosh to induce labor has been associated with life-threatening complications in the infant, including seizures.
• It’s uncertain whether black cohosh is safe for women who have had hormone-sensitive conditions such as breast or uterine cancer.
• If you take any type of medicine, talk with your health care provider before using black cohosh or other herbal products; some herbs and medicines interact in harmful ways.
• Black cohosh may not be safe for use during pregnancy or while breastfeeding.

Keep in Mind

• Take charge of your health—talk with your health care providers about any complementary health approaches you use. Together, you can make shared, well-informed decisions.
• Federal Regulation of Herbal Products
  • Depending on what’s in them, how they’re intended to be used, and how they’re administered (orally or topically), herbal products are regulated in a variety of ways. Many herbal products intended for oral use are marketed as dietary supplements. The rules for making and distributing dietary supplements are less strict than those for drugs.
  • Unlike drugs, dietary supplements are not approved by the U.S. Food and Drug Administration (FDA) before they are sold to the public. When public health concerns arise about the safety of a dietary supplement or an ingredient including an herb, the FDA can take action to protect the public. Manufacturers and distributors of supplements are responsible for evaluating the safety and labeling of their products before marketing to ensure that they meet all regulatory requirements.

For More Information

• Using Dietary Supplements Wisely
• Know the Science: How Medications and Supplements Can Interact
• Know the Science: How To Make Sense of a Scientific Journal Article

Key References