[St. Johns wort extract as plant antidepressant]

In 1998 a standardized hypericum extract has been approved in Austria and Germany for treatment of mild and moderate depression. The efficacy has been already recognized since 1984 from the German Health Authorities based on traditional knowledge. However, this has been substantiated in the subsequent years in controlled clinical trials. Twenty of these studies including a total of 1787 patients have been filed, among them ten older studies in which hypericum was extracted with ethanol compared to newer studies in which the extract was methanol (LI 160). In the past ten years several controlled clinical trials have been conducted compared with placebo as well as synthetic antidepressants. These studies have shown that the effective dosage is within a range of 600-900 mg extract. The side effects are substantially fewer than with synthetic antidepressants and range within 3%. The most important risk is photosensitization, which is however without clinical relevance in the recommended dosages. Recent pharmacological studies revealed that hypericum extracts have a similar mechanism of action like the selective serotonin reuptake inhibitors (SSRI), however, very likely to a smaller extent.