Why doctors overprescribe antibiotics — even in cases where they’re useless

Colds and flus are caused by viruses. Antibiotics do not treat viruses; they’re designed to treat bacteria. Taking an antibiotic for your cold or flu will not work. No one should ever do it.

Yet despite these very simple facts, many people continue to take antibiotics when they have a cold or flu. It’s one reason behind the rise of antibiotic-resistant bacteria.

But when I wrote about this problem recently, a number of readers pointed out that doctors deserve some blame here. After all, patients can’t take antibiotics unless there’s a physician prescribing them. So why are doctors handing out so many antibiotics, unnecessarily and in large quantities? Why do doctors hand out so many antibiotics during flu season?

They should know better, and yet they do it anyway. I asked a number of experts, and the answer was more complicated than I expected.

One problem is that physicians sometimes aren’t sure what’s sickening their patients, so they prescribe antibiotics as a safeguard. Colds and bronchitis (usually caused by viruses) can look awfully similar to pneumonia (which is commonly caused by bacteria), and a doctor might worry about leaving a patient with untreated pneumonia — a serious illness — no matter how unlikely that diagnosis.

“Medicine is such an imperfect, probability-based science,” said Jason Block, a physician and researcher at Harvard Medical School. “So many times, you can second-guess yourself.”

A 2013 study published in BMC Family Practice found that the more uncertain a doctor was about the diagnosis, the more likely they were to prescribe an antibiotic unnecessarily. Another recent study in the Journal of the American Medical Association found that 71 percent of bronchitis cases are treated with antibiotics.

Patient demand is another reason. Doctors often cite requests from their patients as a driver of unnecessary antibiotics use. They may be overstating this factor — research has shown that fewer than 40 percent of people who went to the emergency room wanted antibiotics — but at the very least, doctors’ perceptions can lead to some unnecessary prescriptions.

Doctors often want to please their patients, and they may not have the time to explain why the drugs aren’t necessary. As Ashish Jha, a physician-researcher at Harvard Medical School, told me, “I completely understand why doctors do this: It’s so much easier to write a prescription than to spend 15 minutes persuading somebody they don’t need antibiotics.”

Doctors even joke that they wish they could just write a placebo in these cases, he added. “Though that raises its own ethical issues.”

Simple exhaustion can play a role, too. In research published last year in JAMA Internal Medicine, doctors found that decision fatigue impairs a clinician’s ability to say no to an inappropriate prescription. Doctors were more likely to write an unnecessary prescription later in the course of the day — when their defenses and clarity of thought were already worn down after seeing several patients. “But even at the beginning of the session,” said lead author Jeffrey A. Linder, a Brigham and Women’s Hospital physician-researcher, “there’s still too much antibiotic prescribing.”

He pointed out that Americans use about double the amount of antibiotics as people in most Scandinavian countries. This tendency to rely on the pills could be at least in part due to America’s love of a quick fix. “From this side of white coat,” Linder said, “you’re confronted with somebody who has taken half a day off of work to come in. It’s unsatisfying to say, ‘You’re going to be sick for a week or two.’ It’s much more satisfying to say, ‘I have the magic pill that’s going to make you better.’”

The trouble is half the time patients don’t get better because they didn’t need the drug in the first place.

Clarification: Pneumonia can be caused by viruses and other microorganisms, not just bacteria.