Extracts of the plant Hypericum perforatum L. (St. John’s wort) have traditionally been used in folk medicine to treat a range of disorders, including mental disorders and nerve pain. The common name, St John’s Wort, derives from its traditional flowering and harvesting on the feast of St John the Baptist in late June.
A newly published meta analysis of the effectiveness of extracts of Hypericum perforatum in treating patients with symptoms of depression has concluded that the extracts are more effective than placebo and are as effective as standard antidepressants with fewer side effects. The study analysed results from 29 randomised, double blind trials (5489 patients) comparing extracts of St. John’s wort with placebo or standard antidepressants on clinical outcomes assessing depressive symptoms. The herbal extracts were found to be as effective as tricyclic or tetracyclic antidepressants and selective serotonin reuptake inhibitors (SSRIs). The original studies were carried out in a number of different countries and it is interesting to note that extracts of St. John’s wort appeared to be considerably more effective in German-speaking countries. Hypericum contains a number of compounds that could contribute to its pharmacological activity and its precise mechanism of action is unclear.