Despite a long list of warnings over the years about adulterants found in products marketed as dietary supplements, the latest consumer alert from FDA details the agency’s findings that products purchased on Amazon.com and Ebay.com contained active pharmaceutical ingredients (APIs), including prescription drugs, not declared on the labels. In legal terms, the agency considers such products as misbranded and adulterated, but its urgency is to warn of potential side effects and interactions with prescriptions and legal dietary supplements consumers may be taking.

“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,” said Donald D. Ashley, J.D., director of the Office of Compliance in the FDA’s Center for Drug Evaluation and Research, via press release. “We continue to urge stores, websites and online marketplaces, like Amazon and eBay, to take appropriate steps to protect the American public by not selling or facilitating the sale of illegal FDA-regulated products.”

FDA reported 20 of 25 sex and weight-loss products bought on Ebay were tainted, while all 26 products purchased on Amazon contained undeclared APIs such as undeclared active ingredients, including sildenafil, tadalafil, vardenafil, sibutramine, desmethylsibutramine, phenolphthalein and/or fluoxetine. Many of these products had names similar to products previously warned as adulterated, misbranded and unapproved new drugs by FDA. Several were designated as “Amazon Choice” or “#1 Best Seller,” according to the agency.

An Amazon.com spokesperson assured, via email, “Selling Partners are required to follow all applicable laws, regulations, and Amazon policies when listings items for sale in our store. We have proactive measures in place to prevent prohibited products from being listed and we continuously monitor our store. Those who violate our policies are subject to action including potential removal of their account. We are reviewing the information from the FDA and are taking action accordingly.”

Ebay did not respond to request for comment by press time.

Ashley promised, “Protecting the health and safety of Americans is the FDA’s highest priority, and we will remain vigilant and communicate about products and companies that place U.S. consumers at risk.”

FDA advised consumers to reference its tainted products database with the caveat that the database is limited by the agency’s inability to test every such product on the market. It further urged consumers to report any adverse side effects from such products to the MedWatch Adverse Event Reporting system, which can help the agency track and act on noncompliant and potentially dangerous products.