Ten years of herbal medicine studies reviewed
provided by American Psychiatric Association
review of ten years' worth of published data from controlled studies on the effectiveness herbal products St. John's wort, kava, ginkgo biloba, and valerian shows evidence of efficacy in treating psychiatric conditions. This review is published in the September 2000 issue of Psychiatric Services.
Of nine well-controlled and standardized trials on St. John's wort, five suggested that it is more effective than placebo, and four showed that it is equal to low doses of conventional antidepressants.
Several double-blind, placebo-controlled trials of kava showed its effectiveness in the treatment of mild anxiety.
For the treatment of dementia, all but one of 40 controlled trials of ginkgo extracts reviewed found clinically significant improvement in memory loss, concentration, fatigue, anxiety and depressed mood.
Several studies on the effects of valerian showed its efficacy in the treatment of mild insomnia.
The authors note that statistics show one of every three Americans has used herbal remedies. Because herbal products are considered dietary supplements rather than drugs, they are not standardized in the same rigorous process that pharmaceutical products are, they write.
The public should be aware of two things before rushing to take herbal remedies for psychiatric symptoms. First, it is important to recognize that the composition of herbal preparations sold in the US is quite variable, and second, herbal remedies can produce side effects and interact with prescription medications, said Gregory Gray, MD, PhD, of Charles R. Drew University of Medicine and Science (Los Angeles, CA), coauthor of the review.
Individuals taking these preparations should inform their physicians, especially if they are taking other medications.