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St. John's wort

One of the most well-known and studied CAM treatments, St. John's wort is widely used throughout the U.S. and Europe to treat mild to moderate depression.

Mental Health Implications

Eight sources agree: St. John's wort can help with mild to moderate depression.

It is used extensively by prescription in Germany, where randomized studies have shown the proprietary Schwabe St. John's wort formula to be effective in moderate to severe depression. Mischoulon and Rosenbaum suggest that it may be a promising practice for severe depression.

Although many people use St. John's wort as long-term treatment, there is little evidence of long-term safety or efficacy. All of the clinical studies have been short (24-26 weeks at the most), and most have been small.

Another source (Brown et al). notes that St. John's wort also can be a useful treatment for somatoform disorder (somatization disorder and hypochondria) and seasonal affective disorder.

Side Effects & Drug Interactions

If you are considering continuing the use of St. John's wort with psychotropic drugs, you should definitely consult with the prescribing physician. People with complex medical conditions should insist on careful monitoring while taking St. John's wort.

Side Effects

  • May trigger "cycling" in people with bipolar disorder.
  • Other common side effects, such as nausea, loose stools, and sun sensitivity, are easily addressed by taking food with each dose and using sunscreen.
  • There are insufficient data available at this time to recommend use of St. John's wort by children or during pregnancy or breast-feeding.

Drug Interactions

St. John's wort has serious potential interactions with many prescription medications, including antidepressants, birth control medications and others. The use of St. John's wort should always be discussed with the prescribing physician.


St. John's wort is a commonly-taken and well-supported treatment for mild to moderate depression. It may have other benefits, but also has serious risks of drug interactions. Adjunctive use with antidepressants requires caution and strict coordination with the prescribing physician. Long-term use also requires consultation with a health care practitioner.

For detailed information on St. John's wort and other treatments, download the full review.