Black Cohosh Doesn’t Improve Menopausal Vasomotor Symptoms

Although women’s use of herbal and botanical treatments for menopausal symptoms is well documented, the efficacy and safety of these products are unproven. In a 1-year, randomized, double-blind trial, investigators compared three herbal regimens, hormone therapy, and placebo in 351 women (age range, 45–55; 93% white). Eligible participants were in menopause transition or were postmenopausal and had experienced at least two vasomotor symptoms daily as reported on a standardized scale.

The women were randomly assigned to receive black cohosh (160 mg/day), a multibotanical product (with black cohosh, alfalfa, boron, chaste tree, dong quai, false unicorn, licorice, oats, pomegranate, and Siberian ginseng), the multibotanical plus five dietary counseling sessions aimed at increasing soy intake, conjugated equine estrogen (0.625 mg/day) with or without medroxyprogesterone acetate (2.5 mg/day), or placebo. Randomization to hormone therapy was stopped after publication of the Women’s Health Initiative results.

At baseline, the women averaged 6.5 vasomotor symptoms daily (average intensity, 1.8 on a 1–3 point scale). In all groups, baseline characteristics were similar except for BMI, which was lower in the black cohosh group and higher in the hormone group than in the placebo group. The average adjusted number and intensity of daily vasomotor symptoms decreased over time in all groups. No significant differences were observed between placebo and the three herbal treatments on multiple measures of menopausal symptoms at 3, 6, and 12 months with one exception: the multibotanical plus soy group had higher symptom-intensity scores at 12 months. On average, hormone users had about four fewer daily vasomotor symptoms than did placebo recipients (P<0.001).