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St. John’s Wort: Avoid Drug Interactions
St. John’s wort is a plant used as a tea or in capsules to treat mild depression, anxiety, and sleep disorders. Small studies have shown St. John’s wort to be effective at treating mild depression. For example, a review published March 2017 in the Journal of Affective Disorders looked at of 27 clinical trials with a total of 3,808 patients and concluded that the herbal remedy worked as well as certain antidepressants at decreasing symptoms of mild to moderate depression.

But, says Denise Millstine, MD, an internist in the department of integrative medicine at Mayo Clinic in Phoenix, Arizona, “The biggest issue with St. John’s wort is its medication interactions.”

A study published in July 2014 in the Journal of Alternative and Complementary Medicine found that 28 percent of the time St. John’s wort was prescribed between 1993 and 2010, it was administered in dangerous combinations with antidepressant or anti-anxiety medication, statins, the blood-thinning drug warfarin, or oral contraceptives. For example, combining St. John’s wort with an antidepressant can cause serious complications, including a life-threatening increase in the brain chemical serotonin, according to the National Center for Complementary and Integrative Health.

Taking St. John’s wort may also reduce the effectiveness of other medications — including birth control pills, chemotherapy, HIV or AIDS medication, and medicine to prevent organ rejection after a transplant. It’s important to read up on potential drug interactions and talk to your doctor before taking St. John’s wort.