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Last Updated

31 Oct 2002

Source: Los Angeles Times, October 29, 2001. 

Drug of Choice has a Downside

Treatment: Doctors are concerned that widespread, possibly unnecessary, use of the antibiotic Cipro could mean more incidents of the drug's potentially devastating side effects.



Watching a panicked nation stockpile Cipro makes Linda Baldwin want to cry.

"That drug absolutely ruined my life," says the 61year-old Oxnard woman, who was given Cipro and its sister drug, Floxin, for a urinary tract infection in 1996. She blames the drugs for causing blurred vision, excruciating muscle and joint pain and a cascade of other disabling side effects that have left her unable to work or even play with her grandchildren.

The former election technician for Ventura County says, "I never in a million years thought an antibiotic could do this to me. It makes me heartsick watching people on TV grabbing up Cipro when they're not even sick and letting themselves in for so many adverse reactions that their doctors may not even recognize."

Yet thousands, if not millions, are grabbing up Cipro. In recent weeks, public health officials have prescribed the drug to thousands of postal workers, congressional staff members and others possibly exposed to anthrax. And countless more Americans have purchased Cipro on their own, wanting it on hand just in case they develop symptoms of the potentially lethal infection. Cipro's German-based manufacturer, Bayer, says it has cranked up production to make 200 million pills within 60 days, enough to treat 12 million people.

The tremendous potential for misuse of this powerful drug has some health professionals worried. The very strengths that make Cipro and other fluoroquinolone antibiotics -- such as Levaquin and Floxin -- so effective against serious infection also raise their potential for severe side effects. If Americans who have hoarded Cipro decide to inappropriately self-medicate at the first sign of a cold during the upcoming flu season, drug experts say, they will needlessly expose themselves to the risk of an alarming array of adverse reactions.

"Although it's not widely recognized, Cipro and other fluoroquinolones are associated with serious, rapid side effects that can be devastating and sometimes permanent," says Dr. Jay S. Cohen, an associate professor of family medicine at UC San Diego.

Two kinds of side effects are most commonly linked with fluoroquinolones: musculoskeletal problems such as tendinitis, tendon rupture and joint pain, and central nervous system problems such as insomnia, hallucinations, depression and paranoia. "Less well-known are the adverse reactions that affect the peripheral nervous system, such as tingling, burning pain, twitching or spasms," Cohen adds.

Adverse reactions to fluoroquinolones are often simply overlooked-blamed on other factors, for example, says Cohen, who contends that the drugs are much riskier than is widely believed. He has written a report, scheduled for publication in the December issue of the Annals of Pharmacotherapy, documenting severe sensory disturbances associated with fluoroquinolones. Baldwin is one of 45 patients cited in the study.

Although warnings about most of the drug's side effects are listed in the Physician's Desk Reference, Cohen says, "many patients reported that their doctors either failed to recognize the adverse events or dismissed their significance. They were told to continue taking the drug, when it's imperative that someone with these reactions discontinue use immediately unless medical circumstances such as severe infection and no alternative treatment-warrant otherwise."

Public Health Concerns

In recent weeks, public health officials have been struggling to inform Americans that antibiotics other than Cipro -- such as doxycycline and penicillin -- are effective against anthrax and to urge them not to take any antibiotic without the specific advice of a physician and a clear indication that exposure to the organism may have occurred. All antibiotics can cause gastrointestinal disturbances such as stomach upset and diarrhea-and kill "good bugs" in the body, setting the stage for problems such as yeast infections and the growth of drug-resistant bacteria. Yet penicillin and doxycycline are less risky than Cipro, whose very strength makes its side effect profile much wider.

"Cipro is basically a big gun whose benefits outweigh its risks in certain circumstances," says David Flockhart, chief of clinical pharmacology at the Indiana University School of Medicine. He is considered by many to be the country's foremost expert in fluoroquinolone-related side effects. "But the bigger gun you use, the more damage you can expect as collateral." For a variety of reasons -- from anthrax hysteria to incentives from drug companies -- Flockhart says some physicians start with the "big gun" rather than the lower-level antibiotics, such as penicillin, which can be just as effective, less expensive and less risky.

Fluoroquinolones "should absolutely not be given to kids or pregnant women," says Flockhart, since they can interfere with bone growth. Cipro and other fluoroquinolones also have been associated with ruptures of the shoulder, hand and Achilles tendons that required surgical repair or resulted in prolonged disability. This prompted the Food and Drug Administration in 1996 to ask manufacturers to add a warning to package inserts advising patients to discontinue treatment, inform their physicians and refrain from exercise if they experience pain, inflammation or tendon rupture. Some sports medicine specialists now say they avoid prescribing fluoroquinolones to athletes.

Incidence of Side Effects

Although there are no firm figures on how many people have suffered tendon rupture or any other serious adverse reaction to Cipro, the accepted range for common side effects from any drug is 5% and for uncommon side effects is less than 1%, says Daniel AIbrant, a spokesman for the American Pharmaceutical Assn. and president of the health care consulting firm Pharmacy Dynamics in Arlington, Va. This mean that, for every million people who take Cipro, as many as 10,000 might experience the less common-and often most serious-side effects.

One of Cipro's strengths is its ability to penetrate the central nervous system, says Flockhart, who adds that the downside is that this increases the risk of adverse psychological reactions. About 30% of patients given intravenous Cipro and about 10% of those who take oral Cipro tablets may experience psychological side effects, he says. These range from feeling "out of it" to being anxious and jittery to, in extreme cases, having seizures.

These adverse reactions generally go away when the drug is stopped, says Flockhart, who notes that, in rare cases, an underlying psychiatric concern may be exacerbated by the drug and persist.

One of the best known of these cases is the experience of Philadelphia fiction writer Diane Ayres, who in 1992 took a single Floxin tablet that her physician prescribed for a minor urinary tract infection and wound up delirious in the emergency room six hours later.

She is now diagnosed with manic-depressive illness triggered by the powerful antibiotic, for which she has been treated with medication for nine years, says her husband, investigative journalist Stephen Fried. Fried chronicled his wife's struggle as "friendly fire in the war on disease" in the 1998 book "Bitter Pill: Inside the Hazardous World of Legal Drugs."

"Cipro is the quintessential kind of drug that people take like candy because they think all drugs are safe," says Fried, whose original article probing drug safety for Philadelphia magazine received the 1994 National Magazine Award and set off a Food and Drug Administration investigation. "With so many horrible things going on in this world, some people want to believe that if they take this pill, it will protect them. But that's not how it works, and what people don't understand is that these drugs can cause illness."

Mortality of Adverse Drug Reactions

More than 100,000 Americans die each year from adverse drug reactions, making legal drugs the fourth-leading cause of death in the United States, Fried notes. Yet the general public and some physicians often don't consider the risks versus the benefits when selecting medication, he says. Certain people may be at greater risk of experiencing adverse reactions to fluoroquinolones, including the elderly, people with existing psychiatric or neurological symptoms or a history of head trauma, impaired kidney function and those taking certain medications, including caffeine and nonsteroidal anti-inflammatories such as ibuprofen. Fatal reactions have occurred in patients taking Cipro with the asthma drug theophylline.

"A lot of people get these drugs for the most minor infections," says Fried. "But there are a lot of people who should think twice before taking a quinolone for anything."