In some countries extracts of the plant Hypericum perforatum L. (popularly called St. John’s wort) are widely used for treating patients with depressive symptoms.
To investigate whether extracts of hypericum are more effective than placebo and as effective as standard antidepressants in the treatment of major depression; and whether they have fewer adverse effects than standard antidepressant drugs.
Trials were included if they: (1) were randomised and double-blind; (2) included patients with major depression; (3) compared extracts of St. John’s wort with placebo or standard antidepressants; (4) included clinical outcomes assessing depressive symptoms.
The researchers concluded:
“The available evidence suggests that the hypericum extracts tested in the included trials a) are superior to placebo in patients with major depression; b) are similarly effective as standard antidepressants; c) and have fewer side effects than standard antidepressants. The association of country of origin and precision with effects sizes complicates the interpretation.”