Herbal medicines in the treatment of psychiatric disorders: a systematic review.

This paper reports a critical review of 27 herbal medicines and formulas in treating a broad range of psychiatric disorders (in addition to anxiety and depression), including obsessive-compulsive, seasonal affective, bipolar depressive, psychotic, phobic and somatoform disorders. Ovid Medline, Pubmed and the Cochrane Library were searched for pharmacological and clinical evidence of herbal medicines with psychotropic activity. A forward search of later citations was also conducted. Whilst substantial high-quality evidence exists for the use of kava and St John's wort in the treatment of anxiety and depression respectively, currently there is insufficient robust clinical evidence for the use of many other herbal medicines in psychiatric disorders. Phytotherapies which potentially have significant use in psychiatry, and urgently require more research are Rhodiola rosea (roseroot) and Crocus sativus (saffron) for depression; Passiflora incarnata (passionflower), Scutellaria lateriflora (scullcap) and Zizyphus jujuba (sour date) for anxiety disorders; and Piper methysticum (kava) for phobic, panic and obsessive-compulsive disorders. While depression and anxiety are commonly researched, the efficacy of herbal medicines in other mental disorders requires attention. The review addresses current issues in herbal psychotherapy: herbal safety, future areas of application, the relationship of herbal medicine with pharmaceuticals and the potential prescriptive integration of phytomedicines with synthetic psychotropic medicines. Particular attention is given to clinical and safety issues with St John's wort and kava.