Products sold through the Internet are not only illegal but dangerous

Some sexual enhancement products sold on the Internet contain the same ingredients as prescription drugs such as Viagra and are not only illegal but dangerous, the U.S. Food and Drug Administration cautioned.

Erectile dysfunction products can cause a deadly interaction with many heart drugs, notably those containing nitrates.

"The U.S. Food and Drug Administration are warning consumers not to purchase or consume Zimaxx, Libidus, Neophase, Nasutra, Vigor-25, Actra-Rx, or 4EVERON," the agency said in a statement.

"These products threaten the public health because they contain undeclared chemicals that are similar or identical to the active ingredients used in several FDA-approved prescriptions drug products," added Dr. Steven Galson, Director of the FDA's Center for Drug Evaluation and Research.