Cipro to Doxy: Why the Switch?

By Alice Park

No doctor has ever written a prescription as sweeping as the one the Centers for Disease Control penned to head off the anthrax attack: 10 to 60 days of Cipro, a powerful antibiotic in the arsenal of modern medicine, for anyone who might have come anywhere near a spore. Nearly 20,000 Americans are already taking Cipro, and the number was shooting up--by the hundreds or even thousands--every time another anthrax "hot spot" was discovered.

But every blister pack of antibiotics has its downside, and now doctors are bracing for a second wave of bad news--reports of Cipro side effects and whole new breeds of tough, Cipro-resistant germs. That is why the CDC recommended late last week that all those needing antibiotics against anthrax--for treatment and prevention--be given doxycycline, not Cipro. Doxycycline is a powerful antibiotic that tends to have fewer side effects and costs much less than brand-name Cipro.

The Cipro side effects surfaced first in Florida, where staff members at American Media have started to experience stomach pain and foggy heads. Two were hospitalized--one for a severe allergic reaction, the other for a seizure--and many had to switch quickly to other antibiotics. Even members of the CDC working on the anthrax samples have developed Cipro skin rashes.

All antibiotics have side effects, but fluoroquinolones--the family that includes Cipro--have had more than their share of strange ones. Earlier generations of the drugs caused personality changes, cardiovascular complications and ruptured tendons, particularly the Achilles tendon, in a small number of users. Three earlier fluoroquinolones had to be taken off the market. One, Omniflox, was withdrawn after only three months, following dozens of severe reactions, including several deaths.

Doctors stress that the side effects of Cipro, one of the newest fluoroquinolones, are no worse than those of penicillin and tetracyclines. Common complaints associated with the drug are nausea, diarrhea and vomiting. About 3% of patients in clinical trials had to stop taking it because of stomach pain, skin rashes, lightheadedness or headache. Fewer than 1% experienced the more severe events, including the torn tendons, hallucinations and seizures.

Even under the best circumstances, Cipro is not an easy pill to swallow. Dairy products interfere with the drug's absorption, so you need to wait at least two hours before drinking milk or eating yogurt or cheese. Cipro also increases sensitivity to the sun, so to avoid a rash, you need to cover exposed skin when going outdoors.

The more serious consequences are the long-term ones associated with placing tens of thousands of people on any broad-spectrum antibiotic. Overusing these drugs, physicians have long warned, will permit resistant strains to flourish. One of the scariest examples is the appearance in 1997 of a particularly potent strain of staph bacteria resistant to vancomycin, which used to be the last line of defense. It was partly to avert such a catastrophe that the CDC made its decision last week recommending the switch to doxycycline, which is seen as equally effective. "It would certainly be healthier to have a better balance of antibiotics in use in the population now," says CDC director Dr. Jeffrey Koplan. Healthier and, in the long run, smarter.

--By Alice Park