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Black Cohosh: Connection to estrogen and serotonin

Black Cohosh: Connection to estrogen and serotonin

Historical use

Black Cohosh or Actaea racemose has a long history of use among traditional Native American people. Historical names for this herb include Black snakeroot, rattlesnake root, squawroot, bugbane, bugwort. The name bugbane comes from its use as an insect repellant.

Native to Canada and the United States Native American peoples used the herb for colds, cough, rheumatism, depression, kidney disorders, malaria, menstrual disorders; to relieve symptoms such as hot flashes and night sweats associated with menopause; and to induce labour and lactation. Currently, it has gained popularity to promote women’s hormonal balance, for nerve and muscle pain and to promote relaxation. Careful not to confuse Black Cohosh with Blue Cohosh, which although similar in name, are different in effect.

Contemporary Use

Perhaps the most common current use of Black Cohosh is to relieve menopause symptoms, most notably hot flashes. But it is also used for a variety of conditions including for women’s hormone balance, Premenstrual symptoms and menstrual pain, inflammation, muscle and nerve pain, relaxation and for arthritis. Black cohosh has recently come under some scrutiny in the scientific community recently because its mechanism of action was misunderstood. Previously black cohosh was thought to raise estrogen, which explains its use for women in menopause. During menopause estrogen levels fall and why women experience symptoms such as hot flashes, dryness, mood changes and low libido.


Up until recently studies suggested that this use of black cohosh to increase estrogen levels was inconsistent. For example a study conducted by the University’s College of Pharmacy conducted studies on rats whose ovaries (which produce estrogen) were removed and who also received different concentrations of black cohosh to see if the herb would produce estrogen in the rats. The studies demonstrated that the rats given black cohosh showed no changes in estrogen levels, and concluded that it does not raise estrogen levels. However the reasoning is flawed given that black cohosh could affect the ovaries’ production of estrogen. Not having ovaries could be the cause for the rats inability to create any estrogen at all, rather than the lack of effectiveness of the black cohosh.

New connection to serotonin

The is also some confusion as to how black cohosh works. New evidence now suggests that black cohosh affects serotonin pathways. This could be because estrogen increases serotonin and is why women experience a boost in mood, energy and have less pain during ovulation, as well as why they experience symptoms such as headache, mood changes and fatigue although the exact mechanism at work is still somewhat unclear. Some studies suggest that black cohosh binds to serotonin receptors. Serotonin is responsible for many different processes in the body including body temperature regulation, pain, mood and energy. Its ability to regulate body temperature explains why black cohosh is so effective for hot flashes. On the other hand there is a growing connection between serotonin’s ability to mediate the effects of estrogen. When it comes to the central nervous system (CNS), estrogen influences many functions including pain transmission, headache, dizziness, nausea, and depression. Estrogen also can produce changes in bone density, promotes healthy blood vessels and muscle function and the immune system. These new understandings are gaining new confidence for scientists in black cohosh’s effectiveness.

What does it all mean?

If you’re confused don’t worry, we were a little a first too. To keep it simple, there has been a lot of confusion about just how effective black cohosh is, especially when it comes to women’s hormonal health. A lot of this confusion seems to have come from the fact that science didn’t have the whole picture of how it worked, and they are still working out the details. What we do know is that there is a clear connection between black cohosh, estrogen and serotonin. And serotonin and estrogen benefit many different processes in the body including regulating body temperature, mood, energy, bone density, muscle and joint pain, blood vessels, inflammation, the immune system and the nervous system. This explains why black cohosh is effective in many different uses including menopause symptoms especially hot flashes,  for PMS and women’s hormone balance, depression, relaxing muscle and nerve tension, reducing inflammation, pain and arthritic conditions. Herbal medicine has known for decades that black cohosh is an effective remedy for many different conditions and science is just diving into explaining how and why.

Master Formulae Black Cohosh

  • Traditionally used to help relieve menopausal symptoms (NPN 80000544)
  • Traditionally used to relax skeletal muscles and ease nervous tension (NPN 80001115)
  • Traditionally used in Herbal Medicine to help relieve muscle and joint pain associated with rheumatic conditions (such as rheumatoid arthritis, osteoarthritis and/or fibrositis) and of pain associated with neuralgia (such as sciatica). (NPN 80020511)
  • Traditionally used in Herbal Medicine to help relieve the pain associated with menstruation.