Restricted Use of Black Cohosh

I would like some information on Black Cohosh. I've been taking it for menopause but was told you can only take it for 6 months. I would like to know why only 6 months? Can you restart after a period of time or what? I would really appreciate any info you could give me.

Varro Tyler, in "Herbs of Choice" (Pharmaceutical Products Press) states that research indicates Black Cohosh (Cimicifuga racemosa) recommends that since no long-term toxicity studies have been carried out, use of the herb should be limited to six months. This is likely where the 6 month restriction originated.
Black Cohosh is a strong medicine. Herbalists use it in very small doses, and always in combination with other herbs. Overdose can cause nausea and headache.
For information on herbs that can be taken to help balance the body in menopause, please go to our website at www.richters.com, choose "Q&A" from the main menu, then choose "Search Richters Q&A", and enter the word "menopause" for the search.