Extracts of Hypericum perforatum St. John’s wort have been used since ancient times for the treatment of depression. Various clinical trials have shown the superiority of hypericum extract over placebo. On the other hand, the side effects (which can occur when taken in large doses) were mild and occurred at lower frequency than did those of other anti-depressants. However, the specific constituent of hypericum extract that is responsible for the antidepressant effect has not been identified. Moreover, it’s mode of action is not known yet.
Due to the established beneficial effects and low toxicity; supplements containing Hypericum perforatum St. John’s wort extracts are being used widely especially by the patients who are concerned about side-effects of allopathic medicines.