(CBS News) The Food and Drug Administration is cracking down on fraudulent flu drugs.
The agency Friday that this year's early start of a severe flu season has brought the scammers out in full force, selling numerous untested and unapproved drugs that they claim can prevent or cure the flu.
In the past week, the agency has sent nine warning letters to firms marketing flu-fighting products, including an online seller marketing a flu-vaccine alternative, three firms marketing dietary supplements online, and a firm selling an oral spray online and in major retail stores, according to a blog from pharmacist Gary Coody, the national health fraud coordinator at the FDA.
Companies sent warning letters include:
*The University of Berkley, for a since-removed website selling the Berkley-Body-Immune Flu Prevention product, which the site had claimed was "The most effective alternative to the flu shot."
*Discount Online Pharmacy Nameva.com for selling unapproved "Generic Tamiflu"
*Kosher Vitamin Express for marketing two capsules and an extract for protecting or treating the flu with claims such as, "Zahler Abreve...should be taken at the very first sign of a cold or flu symptom. It can also be taken throughout the cold season as an effective preventative ... tonic."
*Oasis Consumer Healthcare, LLC, for questionable health claims for its "Halo"product: "Knowing that Halo has been proven to kill 99.9% of infectious germs, you'll be ready to embrace the sneezers and coughers in your life."
If sellers don't respond in writing to the FDA's warning letter within 15 days, the agency threatened legal action.
"If you buy one of these products, you don't know what you're getting," wrote Coody. "It could be counterfeit, contaminated, or not stored properly to maintain quality. It could also have the wrong active ingredient or no active ingredient at all.
Coody adds that this is nothing new. During the 2009 "swine flu" pandemic, the FDA sent out more than 100 warning letters to sellers fraudulently promoting products that prevented H1N1. Even during the 1918 Spanish flu pandemic that killed about 675,000 Americans, bogus remedies were rampant he said.
"FDA can't track down all of these fraudulent products, so consumers need to beware of unapproved products that make false claims," according to Coody. "When in doubt about a product, talk to your doctor, pharmacist, or other health care professional."
Government agencies still say the best, approved way to prevent the flu is through a flu vaccine.
Recent estimates from the Centers for Disease Control and Prevention show influenza is still an epidemic in the U.S., but fewer states are reporting disease activity. The CDC continues to urge high-risk people, including those who are 65 and older and those with underlying medical conditions, to seek antiviral flu treatment quickly if they develop flu symptoms. Antiviral drugs like Tamiflu and Relenza can reduce symptoms and help prevent hospitalization.
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