View All Services
Find a New Primary Care Provider
Search by Specialty
View All Locations
Discover classes, events, tours, and groups that fit your interests.
Home > Be Healthy > Health Library > St. John's Wort
St. John's wort ( Hypericum perforatum) is a plant with yellow flowers that people in European countries have used for centuries to treat mild to moderate depression. In the United States, it is sold as a dietary supplement and can be found at health food stores and pharmacies.
St. John's wort is used in the short-term treatment of mild to moderate depression.
It may take up to 2 to 3 weeks for St. John's wort to improve depressive symptoms. Not all preparations of St. John's wort are the same. A standardized form means the amount of St. John's wort is the same in every capsule.
St. John's wort causes fewer side effects (such as digestive discomfort or headaches) than antidepressant medicines, although it may cause a rash with sun exposure.
St. John's wort may interact with medicines used to treat some other illnesses, such as AIDS. It is important to let your doctor or pharmacist know if you want to try St. John's wort so that he or she can determine whether it might interfere with other medicines you are taking.
The U.S. Food and Drug Administration (FDA) does not regulate dietary supplements in the same way it regulates medicines. A dietary supplement can be sold with limited or no research on how well it works.
Always tell your doctor if you are using a dietary supplement or if you are thinking about combining a dietary supplement with your conventional medical treatment. It may not be safe to forgo your conventional medical treatment and rely only on a dietary supplement. This is especially important for women who are pregnant or breastfeeding.
When using dietary supplements, keep in mind the following:
Other Works Consulted
Bongiorno PB, Murray MT (2013). Hypericum perforatum (St. John's wort). In JE Pizzorno, MT Murray, eds., Textbook of Natural Medicine, 4th ed., pp. 833–841. St. Louis: Mosby.
Linde K, et al. (2008). St. John's wort for major depression. Cochrane Database of Systematic Reviews (4).
St. John's wort (2010). In A DerMarderosian et al., eds., Review of Natural Products. St. Louis: Wolters Kluwer Health.
Szegedi A, et al. (2005). Acute treatment of moderate to severe depression with hypericum extract WS 5570 (St. John's wort): Randomised controlled double blind non-inferiority trial versus paroxetine. BMJ, 330(7490): 503–508.
Current as of: April 9, 2019
Author: Healthwise StaffMedical Review: Adam Husney MD - Family Medicine
Current as of:
April 9, 2019
Medical Review:Adam Husney MD - Family Medicine
To learn more about Healthwise, visit Healthwise.org.
© 1995-2019 Healthwise, Incorporated. Healthwise, Healthwise for every health decision, and the Healthwise logo are trademarks of Healthwise, Incorporated.