St. John’s Wort (Hypericum perforatum)

Hypericum perforatum L. also known as St John’s wort (SJW) is an effective dietary supplement for treating various nervous system related disorders. It overcome anxiety, mild to moderate depression, mood disorders and stress due to the presence of vast number of bioactive compounds. As such, hypericin and hyperforin are the major compounds along with other less abundant compounds such as flavonoids, biflavonoids, phloroglucinols, napthodianthrones, xanthones, proanthocyanidins, phenolic acid, etc. Beside its effect over nervous system, SJW also effective against cancer, oxidative stress, inflammation and microbial infections. It is one of the high selling natural supplements in USA and other western countries. However, interaction of SJW with other medicines such as warfarin, phenoprocumon, cyclosporine, oral contraceptives, theophylline, digoxin, indinavir and lamivudine have been reported and thus cautions must be taken while using these medicines along with SJW. This book chapter highlighted the phyto-pharmacological activity of SJW along with its distribution, market value and interactive effect with other medicines for better understanding of its use as nonvitamin nonmineral nutritional supplement.