St. John's Wort
This article provides basic information about the herb
St. John's wort
--common names, uses, potential side effects, and resources for more
information. St. John's wort is a plant with yellow flowers.
Common Names--St. John's wort, hypericum, Klamath weed, goat weed
Latin Name--Hypericum perforatum
What It Is Used For
- St. John's wort has been used for centuries to treat
mental disorders and nerve pain.
- In ancient times, herbalists wrote about its use as a sedative and a
treatment for malaria, as well as a
balm for wounds, burns, and insect bites.
- Today, St. John's wort is used by some for
depression, anxiety, and/or
How It Is Used
The flowering tops of St. John's wort are used to prepare teas and tablets
containing concentrated extracts.
What the Science Says
- There is some scientific evidence that St. John's wort is useful for
treating mild to moderate depression. However, two large studies, one
sponsored by NCCAM, showed that the herb was no more effective than placebo
in treating major depression of
- NCCAM is studying the use of St. John's wort in a wider spectrum of mood
disorders, including minor depression.
Side Effects and Cautions
- St. John's wort may cause increased sensitivity to
sunlight. Other side effects can include anxiety, dry mouth, dizziness, gastrointestinal
symptoms, fatigue, headache, or sexual dysfunction.
- Research shows that St. John's wort interacts with some drugs. The herb
affects the way the body processes or breaks down many drugs; in some cases,
it may speed or slow a drug's breakdown. Drugs that can be affected include:
- When combined with certain antidepressants, St.
John's wort may increase side effects such as nausea, anxiety, headache, and
- St. John's wort is not a proven therapy for
depression. If depression is not adequately treated, it can become severe.
Anyone who may have depression should see a health care provider. There are
effective proven therapies available.
- It is important to inform your health care providers about any herb or
dietary supplement you are using, including St. John's wort. This helps to
ensure safe and coordinated care.
SOURCE: National Center for Complimentary
and Alternative Medicine, National
Institutes of Health
References: National Center for
Complementary and Alternative Medicine. St.
John's Wort and the Treatment of Depression. National Center for Complementary
and Alternative Medicine Web site. Accessed June 30, 2005.
St. John's Wort. Natural Medicines Comprehensive Database Web site. Accessed
June 30, 2005.
St. John's wort (Hypericum perforatum L.). Natural Standard Database Web
site. Accessed June 30, 2005.
St. John's wort. In: Blumenthal M,
Goldberg A, Brinckman J, eds. Herbal
Medicine: Expanded Commission E Monographs. Newton, MA: Lippincott Williams &
De Smet PA. Herbal remedies. New England
Journal of Medicine.
Hypericum Depression Trial Study Group.
Effect of Hypericum perforatum (St. John's wort) in major depressive disorder: a
randomized controlled trial. Journal of the American Medical Association. 2002;287(14):1807-1814.
Last Editorial Review: 8/18/2006