The seized products, valued at more than $100,000, contain undeclared active ingredients found in FDA-approved prescription drugs for ED, or similar substances. Use of these products may result in serious side effects and may interact in dangerous ways with medications that a consumer may already be taking.

“The FDA will not tolerate companies marketing unapproved drugs — products that have not proven to be safe or effective — as dietary supplements,” said Margaret O’K. Glavin, associate commissioner for regulatory affairs. “The agency will pursue necessary legal action to make sure companies and their executives manufacture and distribute safe drug products.”

The seized products, which originated in China, are packaged and distributed by Shangai Distributors, Inc. of Coamo, Puerto Rico. Although the products’ labels state they are natural supplements, these products are drugs and their sale is illegal without FDA approval. Before a new drug product may be legally marketed, it must be shown to be safe and effective.

In response to a consumer complaint, the FDA conducted an inspection of Shangai Distributors Inc., in November 2007. The FDA’s investigation and testing revealed that the seized products contained active drug ingredients found in FDA-approved ED prescription drugs and/or a substance with a structure similar to such drugs that may cause similar side effects and drug interactions. None of the drug ingredients are listed on the labels of any of the seized products.

The undeclared ingredients in these products may interact with nitrates found in some prescription drugs (such as nitroglycerin) and can lower blood pressure to dangerous levels. Consumers with diabetes, high blood pressure, high cholesterol, or heart disease often take nitrates. ED is a common problem in men with these medical conditions. Because they may have been advised against taking ED drugs, they may seek out products like these because they are marketed as “all natural” or as not containing the active ingredients in approved, prescribed ED drugs. Additionally, because the manufacturing source of the active ingredients in these products is unknown, consumers should be aware that the safety, efficacy, and purity of these ingredients can not be validated.

Despite being advised of the findings and the potential adverse health risk posed by the seized products and that regulatory action was possible, the company did not take any action to correct the violations. The FDA issued a press release on December 28, 2007 advising consumers not to buy or use the products. Prior to the seizure, the Puerto Rico Department of Health embargoed the seized products to protect the citizens of Puerto Rico and to support the FDA’s enforcement actions.

The FDA advises consumers who have used any of these products to discontinue use and consult their health care providers if they have experienced any adverse events that they believe are related to the use of these products.

In addition, the FDA plans to require the same changes in labeling for the drug Revatio, also a member of this drug class known as phosphodiesterase type 5 (PDE5) inhibitors. Revatio is used to treat pulmonary arterial hypertension (PAH). PAH is a serious medical condition in which continuous high blood pressure in arteries of the lungs weakens the heart muscle and often leads to right heart failure and death.

The FDA asked manufacturers of these drugs to revise product labeling after a very small number of patients taking the PDE5 inhibitors reported sudden hearing loss, sometimes accompanied by ringing in the ears and dizziness.

“Because some level of hearing loss is usually associated with the aging process, patients on these drugs may not think to talk to their doctor about it,” said Janet Woodcock, M.D., FDA’s deputy commissioner for scientific and medical programs, chief medical officer, and acting director of its Center for Drug Evaluation and Research.

Patients taking Cialis, Levitra, or Viagra who experience sudden hearing loss should immediately stop taking the drug and seek prompt medical attention. Those using Revatio should continue taking their medication but should contact their health care provider for further evaluation. Because Revatio is used to treat a potentially life-threatening condition, the FDA does not recommend patients abruptly stop taking this medication but should consult their physician if they experience sudden problems with their hearing.

A case report in the April 2007 issue of the Journal of Laryngology & Otology involving sudden hearing loss in a man taking Viagra prompted the FDA to search the FDA’s Adverse Events Reporting System for instances of hearing loss and PDE5 inhibitors. The FDA found a total of 29 postmarketing reports of sudden hearing loss, both with and without accompanying ringing in the ears, vertigo, or dizziness. In most of the cases, the hearing loss involved one ear. The hearing loss was either a partial or complete loss of usual hearing. In approximately one third of cases, the event was temporary. In the remainder, the hearing loss was ongoing at the time of the report or the final outcome was not described.

Although no causal relationship has been demonstrated, the strong relationship between the use of these drugs and sudden hearing loss in these cases warrants revisions to the product labeling for this drug class.