Although alternatives exist, "Cipro is the latest and greatest, so it tends to get attention," says Darrell Galloway, a professor of microbiology at Ohio State University.
It helped that Cipro was the only drug approved by the Food and Drug Administration to treat inhaled anthrax. But Health and Human Services Secretary Tommy Thompson today encouraged the use of two other antibiotics, penicillin and doxycycline.Before this month, Cipro -- the brand name for the drug ciprofloxacin -- was little known outside of doctor's offices and pharmacies, where it is dispensed to treat a variety of diseases, including urinary tract infections.
Like other antibiotics, Cipro kills harmful bacteria in the body. The main difference is that it's designed to attack a variety of types of germs. "It is effective against a wide range of organisms," says Bruce Anderson, director of the Maryland Poison Center.
Doctors sometimes use Cipro when they are waiting to find out exactly what type of bacteria they're dealing with. It's especially effective against anthrax because it may take days for scientists to discover what kind of strain is involved in an attack.
"People reach for Cipro because some of the strains engineered by other countries have been engineered to be resistant to many antibiotics," says Dr. Keith S. Kaye, an infectious diseases physician and epidemiologist at Duke University. "I don't think there's anything magical to Cipro if you have a strain that's susceptible to several antibiotics."
According to experts, all known strains are vulnerable to Cipro, although the drug must be given before symptoms develop or shortly thereafter to be most effective.
Before Cipro came along, penicillin was a common treatment for anthrax. "It's not that the other ones don't work," says Anderson. "It's just that the folks who make Cipro [the German drug giant Bayer] are the only ones who have gone through the cost of getting an [approval] from the FDA."
"Using Cipro for five or six days, then moving on to doxycycline or penicillin is not only an effective [treatment] but is also better for your body," Thompson says.
Pharmaceutical companies say they're ready to ramp up production of anti-anthrax drugs if needed, Thompson adds. "This should reassure people that medicine will be available when they need it. We have the drugs."
The United States has a stockpile of Cipro that would serve 2 million people for 60 days, Thompson says. Officials will buy more drugs, including penicillin and doxycycline.
Penicillin and its sister drugs, which cost as little as 12 cents a pill, are available in a generic form. Cipro, which can only be produced by Bayer, costs $4.30 a pill, and two a day are required.
As a back-up plan, some experts are pushing for immediate investigation of anti-toxins, which could be used to treat anthrax. They are reportedly available in China and could potentially be approved quickly here.
Anti-toxins, which could be used after a victim is infected, target the poisons that anthrax bacteria spread through the bloodstream. They prevent the bacteria from stimulating the immune system so much that it sends the body into deadly toxic shock, says Robert C. Liddington, a biologist who studies anti-toxins at Burnham Instate in San Diego.
"You could take them late in the infection, and they'd be able to save your life," he says.
But human bodies can get sick from taking anti-toxins, which are produced by giving anthrax to an animal like a horse. Galloway, the Ohio State University professor, says pills are better than anti-toxins. "It's just technically easier to give a pill than [an anti-toxin]. There are people talking about this seriously, and it can be a lifesaving measure. But on a large scale, I think it might a challenging situation to get into."
What To Do
Don't take any antibiotics without a doctor's prescription. If you haven't been exposed to anthrax, you don't need antibiotics, and experts say they could do more harm than good.