Black cohosh is an herb. The root of this herb is used for medicinal purposes. Black cohosh was first used for medicinal purposes by Native American Indians, who introduced it to European colonists. Black cohosh became a popular treatment for women’s health issues in Europe in the mid-1950s.
Since that time, black cohosh has commonly been used to treat symptoms of menopause, premenstrual syndrome (PMS), painful menstruation, acne, weakened bones (osteoporosis), and for starting labor in pregnant women.
Black cohosh has also been tried for a lot of additional uses, such as anxiety, rheumatism, fever, sore throat, and cough, but it is not often used for these purposes these days.
Some people also apply black cohosh directly on the skin. This is because there was some thought that black cohosh would improve the skin’s appearance. Similarly, people used black cohosh for other skin conditions such as acne, wart removal, and even the removal of moles, but this is seldom done anymore.
Black cohosh also goes by the name “bugbane” because it was once used as an insect repellent. It is no longer used for this purpose. Frontiersmen had said that black cohosh was useful for rattlesnake bites, but no modern researchers have tested this.
Do not confuse black cohosh with blue cohosh or white cohosh. These are unrelated plants. The blue and white cohosh plants do not have the same effects as black cohosh, and may not be safe.
How does it work?
The root of black cohosh is used for medicinal purposes. Black cohosh root contains several chemicals that might have effects in the body. Some of these chemicals work on the immune system and might affect the body’s defenses against diseases. Some might help the body to reduce inflammation. Other chemicals in black cohosh root might work in nerves and in the brain. These chemicals might work similar to another chemical in the brain called serotonin. Scientists call this type of chemical a neurotransmitter because it helps the brain send messages to other parts of the body.
Black cohosh root also seems to have some effects similar to the female hormone, estrogen. In some parts of the body, black cohosh might increase the effects of estrogen. In other parts of the body, black cohosh might decrease the effects of estrogen. Estrogen itself has various effects in different parts of the body. Estrogen also has different effects in people at different stages of life. Black cohosh should not be thought of as an “herbal estrogen” or a substitute for estrogen. It is more accurate to think of it as an herb that acts similar to estrogen in some people.
Possibly Effective for:
- Menopausal symptoms. Research shows that taking some black cohosh products can reduce some symptoms of menopause. But the benefits are only modest. Black cohosh might lessen the frequency of hot flashes. Most of this research is for a specific commercial black cohosh product, Remifemin. The benefits may not occur with all products that contain black cohosh.
Research using black cohosh products other than Remifemin have not always shown benefits for menopausal symptoms. Some of these studies show that these other black cohosh products do not reduce hot flashes or menopausal symptoms any better than a sugar pill (“placebo”).
Some women take black cohosh for hot flashes related to breast cancer treatment. Women with breast cancer should not use black cohosh without talking to their cancer specialist or other health provider. Some early research suggested that black cohosh might reduce hot flashes in breast cancer patients, but more recent and higher quality research shows that black cohosh does not reduce hot flashes in women with breast cancer. Also, there is some question as to whether black cohosh is safe for women with breast cancer. It is important for a woman with breast cancer to discuss any use of black cohosh with her health provider before using it.
- Induction of labor. Some people report that black cohosh can help start labor. As many as 45% of nurse-midwives use black cohosh to start labor in pregnant women at term. Despite its common use, there is no reliable scientific evidence that black cohosh works for this purpose.
- Weak bones (Osteoporosis). There has been some research in women who are past menopause and take a black cohosh product called Klimadynon or Menofem. These products might lead to improved bone formation. However, bone formation is only part of the larger picture related to weak bones or osteoporosis. Bone material is constantly being broken down and rebuilt by the body. Some black cohosh products can lead to increased bone formation, but the newly formed bone may not be as strong as desired. Researchers often look to see whether the persons taking a particular product have fewer fractures over a period of time. They also look to see which bones break the most. For example vertebrae and leg bones may be affected differently. It is not known if black cohosh decreases the chance of developing weak bones or if it prevents bone fractures.
- Bug bites.
- Mole removal.
- Painful menstruation.
- Premenstrual syndrome (PMS).
- Snake bite.
- Sore throat.
- Wart removal.
Side Effects & Safety
Black cohosh is POSSIBLY SAFE when used appropriately by adults.
Black cohosh can cause some mild side effects such as stomach upset, cramping, headache, rash, a feeling of heaviness, vaginal spotting or bleeding, and weight gain.
There is also some concern that black cohosh may be associated with liver damage. It is not known for sure if black cohosh actually causes liver damage. Researchers are studying this. Until more is known, people who take black cohosh should watch for symptoms of liver damage. Some symptoms that may suggest liver damage are yellowing of the skin and eyes (jaundice), unusual fatigue, or dark urine. If these symptoms develop, black cohosh should be stopped and a health provider should be contacted. People who take black cohosh should talk with their health provider about getting tests to make sure their liver is working well.
Special Precautions & Warnings:Pregnancy or breast-feeding: Black cohosh is POSSIBLY UNSAFE when used during pregnancy or breast-feeding. Since black cohosh acts somewhat like a female hormone it might increase the risk of miscarriage.
Breast cancer: There is some concern that black cohosh might worsen existing breast cancer. Women who have breast cancer or who have had breast cancer in the past, and women at high-risk for breast cancer, should avoid black cohosh.
Endometriosis, fibroids, ovarian cancer, uterine cancer, and other hormone-sensitive conditions: Black cohosh acts somewhat like the female hormone, estrogen, in the body. There is some concern that it could worsen conditions that are sensitive to female hormones. Do not take black cohosh if you have a condition that could be affected by female hormones. These conditions include ovarian cancer, uterine cancer, endometriosis, fibroids, and other conditions.
Liver disease: Some reports suggest that black cohosh might cause liver damage. It is not known for sure if black cohosh is the cause of liver damage in these cases. Until more is known, people with liver disease should avoid taking black cohosh.
Kidney transplant: Taking a product containing black cohosh plus alfalfa has been linked to a report of kidney transplant rejection. It is not known if black cohosh is the cause of this rejection. Until more is known, people who have received a transplant should avoid black cohosh.
Protein S deficiency: People with a condition called protein S deficiency have an increased risk of blood clots. Due to the hormone-like effects of black cohosh, there is some concern that black cohosh might also increase the risk of blood clots. There is a report linking blood clots in someone with protein S deficiency after taking black cohosh along with several other herbal products. Until more is known, people with protein S deficiency should avoid black cohosh.
Moderate Interaction Be cautious with this combination
- Atorvastatin (Lipitor) interacts with BLACK COHOSH
There is concern that black cohosh might harm the liver. Taking black cohosh with atorvastatin (Lipitor) might increase the chance of liver damage. However, there is not enough scientific information to know if this is an important concern. Before taking black cohosh talk to your healthcare provider if you take atorvastatin (Lipitor).
- Cisplatin (Platinol-AQ) interacts with BLACK COHOSH
Cisplatin (Platinol-AQ) is used to treat cancer. There is some concern that black cohosh might decrease how well cisplatin (Platinol-AQ) works for cancer. Do not take black cohosh if you are taking cisplatin (Platinol-AQ).
- Medications changed by the liver (Cytochrome P450 2D6 (CYP2D6) substrates) interacts with BLACK COHOSH
Some medications are changed and broken down by the liver.
Black cohosh might decrease how quickly the liver breaks down some medications. Taking black cohosh along with some medications that are change by the liver can increase the effects and side effects of your medication. Before taking black cohosh talk to your healthcare provider if you take any medications that are changed by the liver.
Some medications that are changed by the liver include amitriptyline (Elavil), clozapine (Clozaril), codeine, desipramine (Norpramin), donepezil (Aricept), fentanyl (Duragesic), flecainide (Tambocor), fluoxetine (Prozac), meperidine (Demerol), methadone (Dolophine), metoprolol (Lopressor, Toprol XL), olanzapine (Zyprexa), ondansetron (Zofran), tramadol (Ultram), trazodone (Desyrel), and others.
- Medications that can harm the liver (Hepatotoxic drugs) interacts with BLACK COHOSH
There is concern that black cohosh might harm the liver. Taking black cohosh along with medication that might also harm the liver can increase the risk of liver damage. Do not take black cohosh if you are taking a medication that can harm the liver.
Some medications that can harm the liver include acetaminophen (Tylenol and others), amiodarone (Cordarone), carbamazepine (Tegretol), isoniazid (INH), methotrexate (Rheumatrex), methyldopa (Aldomet), fluconazole (Diflucan), itraconazole (Sporanox), erythromycin (Erythrocin, Ilosone, others), phenytoin (Dilantin), lovastatin (Mevacor), pravastatin (Pravachol), simvastatin (Zocor), and many others.
The following doses have been studied in scientific research:
- Menopausal symptoms: 20-80 mg once or twice daily.
- Weak bones (Osteoporosis): 40 mg daily.