Hypericum perforatum: nature's mood stabilizer.

Hypericum perforatum (HP), better known as St. John's Wort, has been used clinically for centuries. Modern usage is still quite diverse and includes kidney and lung ailments, insomnia and depression. Standardised extracts of HP are widely used in the treatment of psychovegetative disorders and especially for mild forms of depression. Several bioactive constituents of this plant may play important role in its well-known antidepressant activity, which are discussed in the present article. Furthermore, emphasis is also given on its botany, chemistry, pharmacology and clinical efficacy.