What the research says

Research on St. John's wort use for specific conditions shows how the supplement may affect those conditions:

• Depression. Many studies have found St. John's wort to be helpful in treating mild to moderate depression. In fact, some research has shown the supplement to work as well as many prescription antidepressants. It's unclear whether the supplement helps treat severe depression.

  St. John's wort interacts with many medicines. So it might not be a suitable choice, especially if you take any prescription medicines.

• Menopause symptoms. Some research suggests that taking St. John's wort alone or with black cohosh or other herbs might lessen menopause symptoms such as hot flashes.
• Somatic symptom disorder. Some studies have found that St. John's wort might help treat this condition. Somatic symptom disorder causes severe anxiety about physical symptoms such as pain, weakness, and shortness of breath.