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St. John’s Wort

By

Laura Shane-McWhorter

, PharmD, University of Utah College of Pharmacy

Medically Reviewed Jan 2022 | Modified Sep 2022
VIEW PROFESSIONAL VERSION
Topic Resources

What is St. John’s wort?

What claims are made about St. John’s wort?

Does St. John’s wort work?

A number of placebo-controlled studies have been done on St. John’s wort. Overall, these studies show St. John’s wort may benefit people with mild to moderate depression and may even be as effective as some traditional antidepressants. However, most studies do not show that St. John's wort is effective for major depression.

The effectiveness of St. John’s wort in treating ADHD or skin disorders has not been well-studied and is considered unproved.

St. John's wort may help relieve menopausal symptoms such as hot flashes.

What are the possible side effects of St. John’s wort?

St. John’s wort may increase sensitivity to sunlight. Other side effects include dry mouth, constipation, fatigue, confusion, and, in people with bipolar disorder, mania.

During pregnancy, St. John’s wort increases muscle tone in the uterus and thus may increase the risk of a miscarriage.

What drug interactions occur with St. John’s wort?

One of the larger problems with St. John’s wort is that it interacts negatively with a number of drugs people take (see table Drug Interactions With St. John's Wort Some Drug Interactions With St. John's Wort Some Drug Interactions With St. John's Wort ). These interactions may lead to toxic reactions or ineffectiveness of the drug.

Table

Recommendations

St. John’s wort may help ease symptoms of anxiety and mild to moderate depression. The American College of Physicians has stated that it may help symptoms of mild to moderate depression and may cause fewer side effects than conventional antidepressants.

However, St. John’s wort interacts negatively with many drugs people take, so they should check with their doctor before taking it. Some countries have banned its use due to the numerous drug interactions.

Pregnant women and people taking drugs for HIV infection should not take St. John’s wort.

Drugs Mentioned In This Article

Generic Name Select Brand Names
No brand name available
NOTE: This is the Consumer Version. DOCTORS: VIEW PROFESSIONAL VERSION
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