Since the first outbreaks of anthrax were reported earlier this month, health officials had been prescribing Cipro (Bayer's brand name for ciprofloxacin) as a first-line treatment to treat or prevent the disease. Cipro is expensive and can lead to sometimes dangerous side effects. But as the anthrax scare has spread, tens of thousands of people are suddenly using it.
Leading doctors, fearing that overuse will eventually make germs resistant to Cipro, now want to prescribe other antibiotics, notably doxycycline. And public health officials agree.
Yesterday, Dr. Ivan Walks, Washington's public health director, said that postal workers who had been exposed to anthrax were being switched to doxycycline. Today, at the recommendation of the Centers for Disease Control and Prevention, all federal offices were also switching from Cipro to doxycycline as a precautionary treatment because it poses a lower risk of side effects, the Associated Press reports.
"There are compelling public health reasons to consider doxycycline as a better choice in the current situation when we have tens of thousands of people on [Cipro]," says Dr. Bradley Perkins, chief of the meningitis and special pathogens branch at the CDC. "We're moving more strongly to use of doxycycline in this particular situation -- where we know that the strains we've been dealing with are susceptible to doxycycline."
Cipro belongs to a potent new class of antibiotics called fluoroquinolones. Fluoroquinolones work by interfering with the bacteria's ability to replicate. They are "broad-spectrum" antibiotics, meaning that they affect a variety of bacteria and are effective for a range of conditions, from urinary tract infections to pneumonia.
But these drugs can induce seizures in people with epilepsy, though other people might be at risk for seizures as well. The chances are about one in 1,000 for the population as a whole, says Dr. Gregory L. Barkley, medical director of the Henry Ford Comprehensive Epilepsy Program in Detroit and an advisor to the Epilepsy Foundation.
Other factors, such as stress or taking caffeine or aspirin, can increase the risk. Once a person has a seizure, there are additional problems. "There are concrete outcomes to having a seizure," says Barkley. The patient can't drive right away, or operate machinery. If you're a postal worker, this means you can't work."
Cipro also is not recommended for children because it could lead to bone development problems. And, like all antibiotics, it's not effective against viruses.
More importantly, Cipro (like other antibiotics) is not effective if you aren't already infected with one of the susceptible bacteria.
"Cipro does not have a vaccine effect," stresses Dr. Stuart Levy, president of the Alliance for the Prudent Use of Antibiotics.
"The bottom line is that you should not use Cipro or any other antibiotic unless you have an infection, a true infection," adds Dr. Tareg Bey, one of only about 200 board-certified medical toxicologists in the United States.
Not only will the drug not work but you may have to put up with some unpleasant side effects, including diarrhea, headaches, even irregular heart rhythm. Such side effects are not common but they do exist.
"The side effects of Cipro are fairly minimal, but on a prolonged usage who knows what we could see," says Levy. At the very minimum, prolonged usage could result in changes to the body's "good" bacteria or, less likely, even liver damage, Levy adds.
"As with any medication, you have to weigh the risks and the benefits," says Bey. "If you have anthrax, then you take Cipro because it's a high-priority problem and you can forget about the side effects you may encounter. But if you don't have any proof that you have an infection, then you're exposing yourself to Cipro side effects without having any benefit."
Even some people who have been exposed to anthrax have stopped taking Cipro because of the side effects, officials say.
There are essentially three phases involved: exposure (you were in an area where anthrax was found), infection (the germ is definitely in your body), and disease (you are sick with symptoms).
The 10,000 or so Americans who have been prescribed Cipro are taking it because there is fear that they have already been infected, not that they will be. They are also all being tested to verify the presence of the germ in their bodies.
"Anyone who is being treated for risk of exposure to anthrax should be tested at the same time," emphasizes Bey. If a test comes back negative, treatment will be stopped. If a test comes back positive for infection, treatment has hopefully begun early enough to defeat the bacteria. In the case of anthrax, this is critical because, given enough time, the bacteria will start producing a potentially lethal toxin.
There is another public health reason why people should not tak Cipro or any other antibiotic indiscriminately. This creates resistant bacteria, one of the major public health issues of the day. These are bacteria that mutate so a particular antibiotic (or sometimes more than one) becomes ineffective. Resistance has become such a serious problem that some hospitals require physicians to obtain special permission before prescribing certain broad-spectrum antibiotics.
Perkins, speaking at a news conference yesterday, says the CDC is concerned about so many people taking one drug at the same time.
"The potential consequences of having this large a number of people on a fluoroquinolone is that we may limit the time that we're able to use the fluoroquinolones as empiric therapy for these important infections . . . Other bacteria that people are carrying may develop resistance to ciprofloxacin," he said. Empiric therapy is a treatment doctors use when they're not sure how susceptible a germ is to a medicine.
The question of whether to prescribe Cipro or doxycycline will be decided on a case-by-case basis, Perkins added.
The issue now is not so much that we'll be breeding resistant anthrax -- there aren't enough active cases for that to happen, say experts -- but that we'll be breeding other types of resistant bacteria such as E. coli.
Because Cipro is a relatively new antibiotic, not much resistance has built up -- at least yet. That is one of the reasons why Cipro is so powerful, particularly with hard-to-treat bacterial illnesses. Health officials would like to keep it that way.
"We're putting in the hands of consumers an extremely valuable antibiotic, which is life-saving for so many patients, especially the sickest," says Levy. "If we lose that antibiotic, we're going to have presumably more deaths from that than from anthrax, which is not to say that we shouldn't be treating anthrax."
"Citizens should take the advice of health care officials or professional health care workers. Taking things in their own hand might worsen the entire situation in case of an infection," Bey adds.
If a person treats himself partially with antibiotics and doesn't get tested, for instance, it's harder to get a positive test later. Incomplete antibiotic treatment might also change the natural course of the disease.
What To Do
For more information on Cipro and epilepsy, visit the Epilepsy Foundation.
The Alliance for the Prudent Use of Antibiotics has a wealth of information on antibiotics, including when and how to take these drugs.