Updated

Sometimes a hand sanitizer will reach too far in its claims. Four companies that say their products, including hand sanitizers, can prevent infection from the superbug MRSA, or methicillin-resistant Staphylococcus aureus, have been issued warning letters by the U.S. Food and Drug Administration, the federal agency announced April 20.

Since the products, which are all nonprescription, claim to prevent disease, they are classified as drugs, which are within the purview of the FDA. The agency said it does not have sufficient evidence that these particular products are safe and effective for these purposes.

Some of the products also advertise that they preventinfection from E.coli and the H1N1 flu virus. But there is not sufficient proof the combination of ingredients in the products, which include plant oils, the chemical benzethonium chloride, and the antimicrobial agent triclosan can actually impede infection from these diseases. The FDA is still evaluating whether triclosan can be used as an antimicrobial.

Alcohol-based sanitizers, on the other hand, are effective in preventing the spread of the seasonal flu, H1N1, colds and other viral- and bacterial-based diseases.

The warning letters explain the companies are marketing these products in violation of federal law.

"MRSA is a serious public health threat. The FDA cannot allow companies to mislead consumers by making unproven prevention claims," said Deborah Autor, director of the office of compliance in the FDA's Center for Drug Evaluation and Research.

The four companies have 15 days to correct the violations cited in the warning letters. Failure to do so may result in legal action, including seizure and injunction, the FDA said.

The warning letters were sent to these companies:
* Tec Laboratories, for Staphaseptic First Aid Antiseptic/Pain Relieving Gel

* JD Nelson and Associates, for Safe4Hours Hand Sanitizing Lotion and Safe4Hours First Aid Antiseptic Skin Protectant

* Dr. G.H. Tichenor Antiseptic Co., for Dr. Tichenor's Antiseptic Gel

* Oh So Clean Inc., doing business as CleanWell Co., for CleanWell All-Natural Foaming Hand Sanitizer, CleanWell All-Natural Hand Sanitizer, CleanWell All-Natural Hand Sanitizing Wipes, and CleanWell All-Natural Antibacterial Foaming Handsoap

The FDA encouraged health care professionals and patients to report any adverse events or side effects from these products to the agency's MedWatch Safety Information and Adverse Event Reporting Program.

Pass it on: Companies that claim their products prevent MRSA have insufficient evidence for their advertisements, the FDA says.

This story was provided by MyHealthNewsDaily, a sister site to LiveScience.

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