Therapeutic plants of Ayurveda: a review of selected clinical and other studies for 166 species.

This paper reports on the results of a literature survey involving 166 different species of plants used in the Ayurvedic pharmacopoeia, based on a sampling of the literature available to us. We found a wide range of clinical and other in vivo studies for many of the plant-based therapies utilized in the Ayurvedic system. Of the 166 plants investigated, 72 (43%) had at least one or more human studies and 103 (62%) had one or more animal studies. These results appear to contradict the generally held notion that herbal remedies used in non-Western systems of botanical medicine have not been evaluated in human or in vivo trials. Some of these studies are not always as large or methodologically rigorous as clinical studies reported in major medical journals. Indeed, a critical assessment of the research according to the standards of evidence-based medicine would eliminate many of these studies for lack of rigor according to criteria of randomization, sample size, adequacy of controls, etc. However, the studies do suggest which species might be appropriate for larger and better-controlled trials in the future. Accordingly, a synopsis of the plants, their therapeutic applications, and their clinical or experimental evaluations is presented.