Review: evidence is incomplete on the benefits and risks of commonly used herbal medicines
QUESTION: What are the benefits and risks of commonly used herbal medicines?
Data sources
Systematic reviews were identified by searching Medline, EMBASE/Excerpta Medica, CISCOM, AMED, and the Cochrane Library (from inception to October 2000), and by contacting experts.
Study selection
Systematic reviews were selected if they included randomised controlled trials (RCTs) done in humans on ginkgo, St John's wort, ginseng, echinacea, saw palmetto, or kava.
Data extraction
Data were extracted on the common and manufacturer names and uses of each herbal medicinal product, type and quality of the systematic reviews, sample sizes, and results.
Main results
2 reviews (of adequate and good quality) of ginkgo showed positive effects on memory impairment, although these results are questionable because of the possibility of publication bias. 2 reviews (of adequate to good quality) of ginkgo showed beneficial effects in dementia. 1 adequate quality review of ginkgo for tinnitus also had questionable results because of the lack of rigorous trials. 1 good quality review of ginkgo for intermittent claudication showed …
