British doctors are launching a study at 30 hospitals that will look at whether it's safe to stop antibiotics early in some patients. (iStock)

The one rule about antibiotics that has been drilled into our heads for generations is that you absolutely must take the full course — or else something very bad might happen.

Is it time to reconsider that advice?

In an opinion piece published in the BMJ on Wednesday, a group of practicing physicians argues that the idea that stopping antibiotics early may be dangerous to the patient and society as a whole is not grounded in strong science and that policymakers, educators and doctors should drop this message.

The question of how people use antibiotics is one of the most critical issues facing modern medicine. Whenever bacteria are exposed to antibiotics, they have the potential to evolve new strains that can withstand the drugs. Failing to take a full course of antibiotics, the logic goes, leaves behind bacteria that have developed some resistance. The rise of resistant “superbugs,” public health officials warn, could lead to a global pandemic if we cannot figure out how to better control our use of the drugs. In June, the World Health Organization took the unprecedented step of creating a controversial “reserve” list of antibiotics that should be restricted and only used in the most dire of circumstances.

Infectious disease experts Martin Llewelyn from the Brighton and Sussex Medical School, Tim Peto from the Oxford Biomedical Research Center and their co-authors argue in the new article that the advice to finish all your antibiotics contradicts the unambiguous fact that it's not underuse but overuse that's creating the resistance problem.

Peto explained in an interview that as far as they could tell, the “full course” idea originated with a speech in 1945 given by Nobel Prize winner Alexander Fleming. Fleming recounted a moving story involving a patient with a streptococcal throat infection who didn't take enough penicillin, and passed it on to his wife, leading to her death from the newly antibiotic-resistant strain.

“The comments were emotional but not based on evidence,” Peto said. “We want the world to do more research so that we have a plan that's more substantiated.”

Several infectious disease experts agreed these are questions worth asking, but that it's premature to drop the decades-old advice.

Lauri Hicks, director of an office that focuses on antibiotics for the U.S. Centers for Disease Control and Prevention, pointed out that there are a number of studies regarding the ideal duration of therapy for specific issues. Regarding ear infections, for example, one study showed that patients taking an antibiotic for five days were more likely to fail treatment than those taking it for the full 10 days. Hicks said there is also evidence that if you don't complete a course of antibiotics, that makes it more likely that bacteria on your body may develop antibiotic resistance and cause a more serious infection down the road.

However, Hicks acknowledged there are certainly “compelling” reasons to think about it differently.

“There are situations where finishing a full course is important. There are also cases where it may not be as important and may end up putting patients at risk if we give them an unnecessary amount of antibiotics,” she said.

Sarah Fortune, a professor of immunology and infectious diseases at the Harvard T.H. Chan School of Public Health, said that for urinary tract infections and typhoid fever, studies have shown one day of drugs is often sufficient — making the normal week-long course overkill in many situations. For tuberculosis, however, stopping antibiotics early has been shown to put patients at risk for making their situation worse.

“This is an important example because it highlights the double-edge sword of treatment shortening,” she said.

If you treat for too short a time, you may end up enriching the environment for antibiotic-resistant organisms, she explained, “and the relative proportion of drug-resistant bugs becomes higher, higher than the host can ever deal with, and then this infection can reemerge as drug resistant.”

Yonatan Grad, in the division of infectious disease at Brigham and Women’s Hospital, said he feels that there are “many opportunities for improvement” in how doctors use antibiotics, and for many types of infections it may well be possible to reduce the duration of treatment without compromising the treatment’s effectiveness. However, he said the suggestion in the new opinion piece that doctors should tell people to stop taking antibiotics when they “feel better” is problematic.

“How are you to judge ‘feeling better’? Symptoms mostly gone? Entirely gone? Some symptoms, but not others?” he said, “This is too vague and subjective a recommendation.”

The last time scientists discovered a truly new antibiotic was in 1984. Here's why. (Pew Charitable Trust)

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