In the New York City area, prescriptions nearly tripled, drug marketing data indicate.
Spurred by news reports on potential bioterrorism, sales of the antibiotic began climbing right after the Sept. 11 air attacks and weeks before the first news of an anthrax case on Oct. 4, according to a national marketing consultant that surveys pharmaceutical retailers.
The numbers are apt to rise more still as they are released in coming weeks, because the latest data go only as far as Oct. 12 — before the last anthrax deaths and widespread Cipro treatment for postal workers.
"I've been trying to hold back my own friends and relatives who are trying to get this stuff," said Dr. Stephen Baum, at Beth Israel Medical Center in New York. He is president of the New York Society of Infectious Diseases.
The run on Cipro is deepening worry about potential shortages of an important drug for fighting many infections, side effects in more patients and the buildup of antibiotic resistance in the germ.
Drug and disease specialists say the winter flu season could aggravate things, because anthrax can create flu-like symptoms. They fear people will start popping stockpiled Cipro for the sniffles, and others will overwhelm the medical system with demands for treatment.
"I can't tell you what my fears are about what this is going to do to the health system. As people start to get their normal coughs and colds, their first thought is going to be ... anthrax," said Daniel Albrant, president of Pharmacy Dynamics, a pharmaceutical consulting company in Arlington, Va. He said flu shots are especially important this year.
The weekly Cipro prescription numbers, which were supplied by drug-marketing consultant NDCHealth of Atlanta, are projected from a survey of 66 percent of the national retail and mail-order market.
Bayer AG, the German-based maker of the drug, has agreed to supply the U.S. government with up to 300 million tablets of Cipro, an antibiotic approved for treatment of anthrax that the government aims to stockpile for potential emergency use.
Bayer said it would ship by year-end an initial 100 million tablets to the Department of Health and Human Services for 95 cents per tablet, or $95 million. It said that price compared to a previously discounted price of $1.77 per tablet paid by the federal government for Cipro.
The government has an option to purchase an additional 200 million tablets of Cipro for the stockpile.
The drugmaker holds U.S. patent protection on Cipro until late 2003.
It agreed to the arrangement after being criticized for not volunteering to permit other firms to make cheaper copycat versions of Cipro for U.S. distribution after numerous Americans contracted anthrax from letters reeived in the mail.
Bayer initially asked between $1.75 and $1.85 a pill, Health and Human Services Secretary Tommy Thompson said late Tuesday. His final offer, Thompson told CNN's "Larry King Live," was less than $1 a pill.
Thompson spokesman Kevin Keane said attorneys for both sides worked late into the night Tuesday on final details.
Bayer just promised the Canadian government to deliver emergency supplies of Cipro, in the event of a bioterrorism attack there, for $1.30 a pill. That agreement apparently ends Canada's threat to suspend Bayer's Cipro patent and buy the medication from a generic producer instead.
Thompson had said he would consider going to Congress to seek a waiver of the patent and allow production of a generic medication if Bayer did not lower its price.
In a related development, pharmaceutical scientists at an international meeting in Denver have warned consumers of the dangers of buying the anti-anthrax drug Cipro off the Internet or in foreign countries.
"You're really playing Russian roulette," said research scientist David Hauss of pharmaceutical giant Eli Lilly and Co. "You may not even be getting the chemical that you think you are getting, or you may be getting the chemical adulterated with unknown harmful impurities."
Health officials have said self-prescribing Cipro could lead to side effects such as dizziness, confusion and depression or resistance to the drug.
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