Products including Medavir, Herpaflor, Viruxo, C-Cure, and Never An Outbreak, were among those targeted in the joint action by the Food and Drug Administration and the Federal Trade Commission.
"These products are dangerous because they are targeted to patients with serious conditions, where treatment options proven to be safe and effective are available," said Deborah Autor, director of the Office of Compliance in FDA's Centre for Drug Evaluation and Research.
"Consumers who buy these products may not seek the medical attention they need and could spread infections to sexual partners."
The agencies "issued multiple letters to companies warning that their products violate federal law," a statement said.
"The joint action is the first step in keeping these unproven items from being sold to the public and preventing consumers from being misled."
Some of the products, sold in retail stores or online, are marketed as "dietary supplements" but since they promise to treat disease they cannot be sold in interstate commerce without an FDA approval for a new drug application.
The statement issued by the FDA did not give details on how many drugs are being targeted, but more information could follow during a press conference later in the day.
The letters notify the companies involved that they have 15 days to correct any violations, or face "legal action, including seizure and injunction, or criminal prosecution," the FDA statement said.
(Reuters Health, May 2011)