Decades of rampant antibiotic overuse — doctors prescribing these drugs unnecessarily, farmers using them to fatten up livestock— has given rise to very serious, sometimes deadly superbugs such as C. difficile, which now sickens half a million Americans every year. In attempt to minimize these threats, there’s been a big push from the federal government and professional physicians’ organizations in recent years to pull back on antibiotic prescribing — except when deemed absolutely necessary. Doctors are now strongly discouraged from writing scripts “just in case” a patient’s congestion or cough stems from a bacterial infection. Instead, they’re supposed to do the appropriate diagnostic testing and then prescribe an antibiotic if that’s truly what’s required.
But besides still penning too many scripts, doctors are contributing to antibiotic resistance by prescribing the “wrong” antibiotics for common illnesses, according to a new report by the Centers for Disease Control and Prevention and the Pew Charitable Trusts. Of the 42 million patients prescribed antibiotics for sinus infections, middle-ear infections, and sore throats each year, almost half are given a broad-spectrum drug such as azithromycin, when they really should be prescribed a more-targeted antibiotic like amoxicillin or penicillin.
The problem is simple: Broad-spectrum antibiotics unnecessarily increase resistance to many more strains of bacteria, says Dr. David Hyun, study co-author and an infectious disease specialist at the Pew Charitable Trusts. “Narrow-spectrum antibiotics are designed to attack a very specific small number or pathogens as opposed to a broad swathe,” he explains. “They are highly effective at treating certain illnesses, and when effectiveness is equal, the preference is always to use a narrow-spectrum treatment.”
Yet many doctors aren’t listening. They’re continuing to prescribe azithromycin, commonly called the Z-Pak, and other newer antibiotics over amoxicillin and penicillin. “Certainly, some of this inappropriate prescribing still stems from lack of awareness,” Hyuan says. “But much of it is driven by social interactions between doctors and patients. Patients pressure doctors for certain antibiotics that they’ve taken in the past, tolerated well, and had success with.”
Additionally, Hyun says some physicians still prescribe antibiotics without making proper diagnoses. They’ll choose a broad-spectrum drug in hopes that it’ll wipe out whichever bug ails the patient. Another factor behind inappropriate prescriptions may be that doctors mistakenly believe the broader-spectrum antibiotics are stronger and more effective for bacterial sinus infections, middle-ear infections, and sore throats.
“I always give the example of strep throat,” says Dr. Jeffrey Linder, an internal medicine doctor at Brigham and Women's Hospital in Boston and contributor to this report. “The bacteria that causes it has never, ever become resistant to penicillin. And yet, ironically, patients ask doctors for something they deem stronger, such as azithromycin, which is in fact resistant to that bug. That goes against both the prescribing guidelines and microbiology.”
Linder blames the widespread misinformation partly on drug companies’ brilliant marketing efforts. “I think this is still an aftereffect of years of advertising these newer antibiotics, whereas nobody has advertised penicillin or amoxicillin probably since the 1950s,” he says. “Because the company did tons of genius marketing around azithromycin, it’s the most commonly prescribed antibiotic in the U.S. Yet it’s not the first-line-recommended antibiotic for any of the infections we looked at, so it doesn’t make good sense to prescribe it.”
Beyond hashing out the risks and benefits of particular antibiotics, Linder insists we need to be wary of this entire class of drugs. “In our other recent research, we found that at least half of prescribed antibiotics were unnecessary in the first place,” he says. “Whether it’s a narrow- or broad-spectrum antibiotic, so many adults and kids are putting chemicals in their bodies that they don’t need. They offer no benefit but can cause harm such as gastrointestinal upset or allergic reactions.”
Linder doesn’t expect every patient to be familiar with prescribing guidelines — that’s physicians’ job. But if you’re sick and need to see your doc, he suggests stating clearly that you want to get checked out but do not automatically expect or even want an antibiotic.