Hypericum for depression. An update of the clinical evidence.

This review is aimed at providing an updated evaluation of the clinical evidence regarding Hypericum perforatum (St. John's wort) as an antidepressant, based on recently published randomised controlled trials. Computerised literature searches revealed six trials published since the metaanalysis by Linde et al. (1996) [Linde, K., Ramirez, G., Mulrow, C.D., Pauls, A., Weidenhammer, W., Melchart, D., 1996. St. John's wort for depression--an overview and meta-analysis of randomised clinical trials. Br. Med. J. 313, 253-258]. The results of these studies provide further evidence that hypericum is superior to placebo in treating mild or moderate depression. However, there is still insufficient evidence to assess the efficacy of hypericum in comparison with conventional, particularly modern, antidepressants. Furthermore, there remains a lack of trials assessing long-term effects, other types of depression and different preparations and doses. It is concluded that recent clinical trials strengthen the case for hypericum as an antidepressant, but more work needs to be done to answer the remaining questions.