Just like the book of love, the road to evidence-based medicine is long and boring. The following is an excerpt from an article on the use of black cohosh as a botanical treatment for menopause and dysmenorrhea. It illustrates the tedious process of coming to a reliable conclusion on not only whether a drug works, but exactly how much is necessary.
In clinical studies before 1996, the dose was […] equivalent to 48–140 mg of black cohosh extract per day. A recent clinical trial comparing two different dosages of Remifemin® (40 mg vs. 127 mg daily), for six months, in 116 women with menopausal complaints, found similar safety and efficacy profiles for both doses (Liske et al., 2002). Based upon the results of this trial, a recommended dose equivalent to 40 mg of black cohosh (dried root) daily is currently recommended (Liske, 1998).