Natural Standard® Patient Monograph, Copyright © 2017 ( All Rights Reserved. Commercial distribution prohibited. This monograph is intended for informational purposes only, and should not be interpreted as specific medical advice. You should consult with a qualified healthcare provider before making decisions about therapies and/or health conditions.


Extracts of Hypericum perforatum L. (St. John's wort) have been recommended traditionally for a wide range of medical conditions. The most common modern-day use of St. John's wort is for depression. Studies have shown St. John's wort may be equally effective as tricyclic antidepressants (TCAs) and selective serotonin reuptake inhibitor (SSRI) antidepressants for mild to moderate depression.

Overall, the evidence suggests St. John's wort may be effective for in mild-to-moderate depression. The evidence for severe depression remains unclear.

St. John's wort may cause serious interactions with prescription drugs, herbs, or supplements. Therefore, people using any medications should consult their healthcare providers, including a pharmacist, prior to starting therapy.

This evidence-based monograph was prepared by The Natural Standard Research Collaboration