Dietary supplements marketed for sexual function — which are supposed to be free of conventional drugs — may contain hidden pharmaceutical ingredients. A study published online Oct. 12, 2018, by JAMA Network Open analyzed almost 800 supplements. Most were for sexual enhancement, weight loss, or muscle building. About 80% of the supplements contained one pharmaceutical ingredient, 20% contained more than one pharmaceutical ingredient, and some (33 products) contained three or more pharmaceutical ingredients. The most common hidden pharmaceuticals: erectile dysfunction drugs, weight-loss medications, antidepressants, anabolic steroids, and nonsteroidal anti-inflammatory drugs. Some of the hidden drugs have never been approved by the FDA; others have been removed from the market. And all, say the authors, have the potential to cause severe harm from accidental misuse, overuse, or interaction with other medications, underlying health conditions, or other drugs within the same dietary supplement. Talk to your doctor first before taking any dietary supplement.