Viagra-like products draw an FDA warning

Some products advertised online as natural alternatives to impotence drugs such as Viagra illegally contain the same active ingredients as prescription medicines, the Food and Drug Administration said Wednesday.

The FDA warned consumers not to buy or use seven of the so-called dietary supplements sold online to treat impotence and enhance sexual performance. The list includes Zimaxx, which FDA testing showed contains sildenafil, the same active ingredient in Viagra. Viagra, made by Pfizer Inc., is sold in the United States only by prescription.

A message left for Herbal Remedies USA, a Casper, Wyo.-based company that sells Zimaxx on its website, was not immediately returned. The FDA has sent letters to the company and five others that warn them about marketing illegal drugs, based on the claims made for the products or their ingredients.

The other products named by the FDA are Libidus, Neophase, Nasutra, Vigor-25, Actra-Rx and 4Everon. Chemical analyses showed the products contain either chemical ingredients that are similar to sildenafil or a second drug called vardenafil, the FDA said. Vardenafil is the active ingredient in Levitra, an impotence drug sold by Glaxo SmithKline PLC and ScheringPlough Corp.