Nearly 50 dietary supplements sold on Amazon and eBay contain active pharmaceutical ingredients, including some prescription drugs, that are not declared on the label and could pose serious risks to consumers, the Food and Drug Administration announced Thursday.

The FDA, which regulates dietary supplements in the U.S., purchased and tested weight loss and sexual enhancement supplements on Amazon and eBay’s websites. The agency found that the products contained a variety of potentially dangerous drugs. Those ingredients could cause serious side effects or interact with medications or supplements a consumer is already taking. Under federal law, dietary supplements must accurately state the product’s ingredients on their label, and they cannot contain drugs.- ADVERTISEMENT -

“While the FDA has engaged in discussions with online marketplaces like Amazon and eBay regarding these issues in the past, we believe they can do more to protect consumers from these fraudulent and potentially dangerous products,” Donald D. Ashley, director of the Office of Compliance in the FDA’s Center for Drug Evaluation and Research, said in a statement. The FDA is urging consumers to avoid the supplements it cited.

Ashley Settle, a spokesperson for eBay, tells Consumer Reports the company is currently reviewing its site and will remove the violative products. Amazon didn’t immediately respond to a request for comment Thursday afternoon.

The findings are the latest in a string of studies that have found undeclared drugs in dietary supplements. A study from the FDA published in June analyzed the contents of 59 bitter orange supplements and found illegal stimulants in almost 10 percent of the products. However, to date the agency doesn’t appear to have publicly warned consumers about that potential risk. In September, researchers from Harvard University reported that they’d found hidden drugs in popular “nootropic” supplements, which are claimed to boost brain function.

In the FDA’s latest testing, all 26 products purchased by the agency on Amazon and 20 bought on eBay contained undeclared pharmaceutical ingredients, according to an FDA news release.

The ingredients included sildenafil (the active ingredient in Viagra), tadalafil (Cialis), and vardenafil (Levitra). The agency also found sibutramine, an appetite suppressant; desmethylsibutramine, an analog of sibutramine; and fluoxetine (Prozac).

“Many of these are active ingredients for use in FDA-approved prescription drugs, which are restricted to use under the supervision of a licensed health care professional,” the agency said in the news release.

The FDA said many of the products the agency purchased have names that are the same as, or similar to, supplements previously found to be tainted with drugs. In late 2018, a database maintained by the FDA listed 776 supplements tainted with undeclared drugs. Now that database lists more than 1,000.

The FDA says that several products purchased on Amazon were designated on their listings as “#1 Best Seller” or “Amazon’s Choice.” The Amazon’s Choice badge is given to “highly rated, well-priced products available to ship immediately,” the company tells shoppers throughout its website.

What You Should Do

The FDA published specific info about each sexual enhancement supplement and weight loss product cited in the announcement.

The agency’s tainted products database includes the names of over 1,000 supplements to be aware of, but note that the FDA cannot test and identify all products on the market today. So the agency and consumer advocates say that you should exercise caution about using supplements marketed for sexual enhancement, weight loss, bodybuilding, and more.

If you’re considering using such products, you should talk with a doctor or another healthcare professional about whether the ingredients may interact with any medications or supplements you’re currently taking. If you experience an adverse event after taking a supplement, the FDA encourages consumers to file a report about what happened with the agency.