Acute bronchitis is generally a result of any number of viruses, meaning that antibiotics won’t work. This is not news to the medical or scientific community, and the Centers for Disease Control and Prevention have been trying for 15 years to get doctors to stop the knee-jerk practice of prescribing antibiotics for the disease. And yet, a new study finds that some 70% of physicians are still telling patients to take drugs that don’t work.

The study, published in the Journal of the American Medical Association, looked at the prescription of antibiotics for acute bronchitis between 1996 and 2010 and found that, in spite of efforts like those taken by the CDC, the rate at which doctors were prescribing the unnecessary drugs actually increased slightly.

“You’re taking a medicine that has no chance of helping you and has a very real chance of harming you,” says study co-author Dr. Jeffrey Linder of Brigham and Women’s Hospital in Boston.

There are several concerns about taking unnecessary antibiotics. First, patients may see unpleasant side effects like diarrhea and nausea. Why would you subject someone to that for a medication that isn’t treating their illness? Second, there’s the larger issue of antibiotic overuse and how it is resulting in medicine-resistant bacteria. Then there’s the fact that you could actually get more ill, as antibiotics can increase the risk of a colon infection called C. difficile.

There are cases in which bronchitis patients might receive antibiotics — either to treat additional ailments or to rule out non-bronchitis illnesses. But the Healthcare Effectiveness Data and Information Set — performance measures used by the healthcare and insurance industry — says the antibiotics prescribing rate for acute bronchitis on its own should be zero.

But the researchers for the JAMA study found that the actual rate is around 71%.

While doctors generally know they shouldn’t be prescribing the drug, there is pressure from patients who believe antibiotics will help them. The study’s co-author also says there are some doctors who believe that patients all want antibiotics.

In order to stop this ill-advised practice, it’s going to take doctors who refuse to give into misinformed patients, and patients who realize there isn’t much you can do for acute bronchitis other than muscle it out.

“If you develop a cough and don’t have a fever and otherwise feel pretty well, the normal duration of cough is three weeks, and taking an antibiotic doesn’t shorten that,” says Dr. Linder.

Most Doctors Prescribe Antibiotics That Don’t Work [BusinessWeek]

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