Black cohosh is a tall perennial herb originally found in the
northeastern United States. Native Americans used it primarily
for women's health problems, but also as a treatment for
arthritis, fatigue, and snakebite. European colonists rapidly
adopted the herb for similar uses. In the late nineteenth
century, black cohosh was the principal ingredient in the wildly
popular Lydia E. Pinkham's Vegetable Compound for menstrual
cramps. Black cohosh’s main use today is for the treatment of
menopausal symptoms. Meaningful but far from definitive evidence
indicates that black cohosh extract might reduce hot flashes as
well as other symptoms of menopause. In the past, black cohosh
was believed to be a phytoestrogen, a plant-based substance that
has actions similar to estrogen. However, as we describe below,
growing evidence indicates that black cohosh does not have
general estrogen-like actions. Rather, it may act like estrogen
only in certain places: the brain (reducing hot flashes), bone
(potentially fighting osteop