Overview

St. John's wort (Hypericum perforatum) is a flowering shrub native to Europe. It gets its name from the fact that it often blooms on the birthday of the biblical John the Baptist.

The flowers and leaves of St. John's wort contain active ingredients such as hyperforin. St. John's wort is available as a supplement in teas, tablets, liquids and topical preparations.

St. John's wort is often used to treat depression and menopausal symptoms.

Evidence

Research on St. John's wort use for specific conditions shows:

  • Depression. Several studies support the therapeutic benefit of St. John's wort in treating mild to moderate depression. In fact, some research has shown the supplement to be as effective as several prescription antidepressants. But because St. John's wort causes many drug interactions it might not be an appropriate choice, particularly if you take any prescription drugs.
  • Menopausal symptoms. Some evidence suggests that taking St. John's wort combined with a particular form of black cohosh extract might reduce menopausal symptoms such as hot flashes. The research is less compelling when St. John's wort is used alone.

Our take

Yellow light: Caution

Caution

St. John's wort can be effective for treating mild to moderate depression. However, the supplement interacts with many medications and can cause serious side effects. Don't use St. John's wort if you take prescription medications.

Oct. 13, 2017