What the Supplement Industry Isn’t Telling You About St. John’s Wort
—By Azeen Ghorayshi
Mon Feb. 13, 2012 2:30 AM PST
The popular herbal depression remedy can interact with other drugs. So why doesn’t its label say so?
St. John’s Wort is a small, yellow-flowered herb whose name derives from one of its first known uses—warding off evil on St. John’s Day, June 24. Now, Americans shell out roughly $55 million a year for SJW at big-time distributors like Whole Foods, GNC, and The Vitamin Shoppe, making it one of the most popular herbal remedies on the market. Usually taken in the form of capsules or tea, the supplement has demonstrated benefits in treating mild to moderate depression. Rather surprising, then, that it’s also been shown to negatively interact with some of the most commonly prescribed pharmaceutical anti-depressants on the market.
Safe to say that’s fairly counter-intuitive, and that it could even be dangerous. What’s more, SJW has also been shown to reduce the efficacy of some oral contraceptives. It’s even suspected to have caused unplanned pregnancies. (One woman reported having been prescribed birth control for over 9 years, and experiencing an unintended pregnancy just 6 months after starting her SJW treatment.)
But lots of drugs have potentially dangerous interactions. The real problem here lies in transparency to consumers—a problem that goes directly back to the supplement’s manufacturers. In a 2008 study published in BMC Complementary and Alternative Medicine that tested 74 different SJW brands, less than a quarter of the product labels identified possible interactions with antidepressants. Even more disturbing was that only 8 percent identified possible interactions with birth control.