Patients should be informed that it might take 4 to 8 weeks to feel an effect. Side effects are rare and include gastrointestinal upset, headache, and dizziness. While the longest study in the literature lasted 12 months, there is no indication that longer use is unsafe.
Breast Cancer Multiple studies showed that black cohosh has an inhibitory effect on estrogen receptor breast cancer cells. One study showed augmentation of the antiproliferative effects of tamoxifen. In a study that looked at the effectiveness of black cohosh in reducing menopausal symptoms for breast cancer patients, both the placebo group and the group receiving black cohosh had a 27% reduction in the number and intensity of hot ﬂashes. Only sweating was significantly more improved in the black cohosh arm (73). In another study, 136 breast cancer survivors were randomized either to tamoxifen alone or tamoxifen plus black cohosh. At 6 months, there were no significant differences, but at 1 year, 47% of women in the intervention arm versus none in the control group were free of hot ﬂashes. Severe hot ﬂashes were reduced in the intervention arm (24%) compared with the tamoxifen-alone arm (74%) (74). Although it is useful to know that black cohosh is not estrogenic, its efficacy in this group of patients is not established.
Many different botanicals use the name ginseng. The two most common are Siberian ginseng (Eleuthero) and oriental or Korean ginseng (Panax). Both of these agents are extracted from the root of their respective plants, and both are used to combat fatigue or to restore “vital force” for performance enhancement.
Panax ginseng is a small perennial that grows in northeast Asia. One study of 12 patients examined its effect on menopausal women, both with and without the symptoms of fatigue, insomnia, and depression. At baseline, the patients with symptoms had significantly higher anxiety states. The dehydroepiandrosterone-sulfate was one-half that of those in the control group, and the cortisol/dehydroepiandrosterone-sulfate ratio was significantly higher in the symptomatic patients. After treatment, the Cornell Medical Index and anxiety state decreased to that of the controls, and the cortisol/dehydroepiandrosterone-sulfate ratio decreased significantly, although not to the level of the control group (75).
In terms of the physiologic symptoms, a randomized, multicenter, double-blind parallel group study compared a standard ginseng extract with placebo. Quality of life and physiologic parameters were assessed at baseline and after 16 weeks of treatment. There was no significant difference in symptom relief and no significant difference in the physiologic parameters of follicle-stimulating hormone, estradiol, endometrial thickening, maturity index, or vaginal pH. Patients did experience significant improvement in depression, sense of well-being, and health (76). A second study demonstrated improvement in fatigue, insomnia, mood, and depression (70).
There is no evidence to support the use of ginseng for relief of physiologic symptoms. If patients are suffering from psychological symptoms of menopause, they may benefit from Panax ginseng. Although its mechanism of action is not clear, Panax ginseng does not appear to be estrogenic. Use of Panax ginseng should be avoided with stimulants, and it may cause headaches, breast pain, diarrhea, or bleeding. The recommended dose is 100 mg of a standardized extract two times daily for 3 of 4 weeks.