Cipro Web sites warned by U.S.

LONDON, England (CNN) -- The U.S. drug authority has warned 11 Web sites, including several in Europe, against selling the anti-anthrax drug Cipro.

The Food and Drug Administration has sent "cyber" letters to the Web sites stating that it could not determine if the drugs being offered met U.S. specifications.

It therefore warns that the sale and distribution of the drugs "may be illegal in this country." Cipro, manufactured by drug company Bayer Corporation, is marketed legally in the US.

Swiss Web site Farmamondo.com, British Mastersmarketing.com, Portuguese Pharmagroup.com and Irish Usamedicine.com were warned on October 31.

They all advertised Cipro, with the Swiss and Irish Web sites stating their product was manufactured by Bayer, while the other two sites did not specify the manufacturer.

An Italian-based company, Farmaciacerati.it, was also warned but did not list Cipro on its site.

Web sites in Canada, Mexico and Malaysia were also warned.

The FDA said it was taking steps to warn U.S. citizens that drugs promoted and sold via the Internet "from foreign sources" may not be approved for marketing and may not be legally imported in the US.

"In our experience, many drugs obtained from foreign sources that purport to be the same as U.S.-approved prescription drugs have been of unknown quantity," the FDA letter said.

Regulatory authorities in the countries where the Web sites operated were also being advised of the potential violations, the FDA said.

There have been four deaths from inhalation anthrax since the September 11 terror attacks in New York and Washington. A total of 16 anthrax cases have been confirmed, including six cases of cutaneous anthrax.

Under an agreement with the U.S. Department of Health and Human Services, Bayer will supply 100 million Cipro tablets to the U.S. government by the end of the year. The U.S. has an option to purchase an additional 200 million tablets.

The government already has a large stockpile of Cipro for use in its fight against anthrax.

Bayer donated two million tablets of Cipro to the department for emergency workers. Another two million tablets have been donated to postal workers who may have been exposed to anthrax-laden envelopes.

Bayer Corporation is part of Bayer Group, a $29 billion international health care and chemicals group based in Germany.