Although it is not new information that the Food and Drug Administration (FDA) doesn’t regulate over-the-counter (OTC) dietary supplements there is recent evidence that consumers should be cautious when purchasing these products. So it turns out that there are many over-the-counter dietary supplements have been found to contain active pharmaceuticals not identified on the label. Yes, your supplements are cheating on you!
Examples include products marketed for weight loss (found to frequently contain sibutramine and phenolphthalein, two drugs previously withdrawn from the market by the US Food and Drug Administration [FDA]), sexual enhancement (found to contain phosphodiesterase-5 inhibitors, most commonly sildenafil, the active chemical in Viagra) and muscle-building supplements (found to contain anabolic steroids).
For my patients I recommend that they purchase third-party verified OTC dietary supplements from reputable sources when they can. This was explained in my blog post about CBD oil. Here is a Consumer Reports article that gives some examples of third-party labs that test OTC products.