Why do so many prescriptions say, “Take for 10 days” or “Take for 7 days”? Well, we have 10 fingers and there are 7 days in a week. These are historic guesses because often the answers haven’t been critically studied. More recently it’s become apparent that urinary and skin infections plus some pneumonias may do quite well with shorter courses. The effort is to contain the development of resistant super-bugs.
From Al MacRae and the WSJ: “Remember the doctor’s advice to always finish your antibiotics, even if you feel better?
That message is being up-ended by concerns that taking antibiotics when they are no longer needed is contributing to the growing danger of antibiotic resistance.
In a recent article in the journal BMJ, a group of infectious disease experts from England argue that doctors should stop making the recommendation because it isn’t based on any evidence. In fact, they note, studies have shown that in some cases — such as pneumonia — shorter courses of antibiotics are just as effective as longer ones.
The longstanding advice to finish a course of antibiotics was based on concerns that the infection wasn’t completely treated and could relapse in a resistant form. “We are challenging this now because antibiotic resistance is such an enormous issue,” says Martin Llewelyn, a professor of infectious diseases at Brighton and Sussex Medical School in England.
The danger with stopping antibiotics too early is recurrence of the infection, not resistance, Dr Llewelyn says.
“We’re not suggesting stopping antibiotics when you feel better is necessarily the right thing to do across the board,” he adds.
The improper use of antibiotics has become a pressing public health issue because it allows bacteria to evolve into new strains that are resistant to the drugs. Earlier this year, the World Health Organisation released a list of the 12 most dangerous of these “superbugs,” and in June updated a list of antibiotics that should be reserved as a last resort.
Doctors prescribe antibiotics for different infections based on clinical guidelines from medical professional societies.
But despite widespread acknowledgment in the infectious disease community that finishing a course of antibiotics isn’t always needed, the message persists in guidance from many health organisations, including the WHO.
A WHO spokesman says it agrees with the BMJ analysis and is reviewing evidence about the ideal course duration for different cases.
Lauri Hicks, director of the office of antibiotics stewardship at the Centers for Disease Control and Prevention, says the organisation changed its guidance about a year ago, to taking an antibiotic as directed by a health care provider.
“We are very interested in identifying opportunities to improve how antibiotics are being used, and that involves making sure the patient gets the right drug, the right dose and the right length of therapy,” she says.
For most infections, she says, the ideal course of therapy is probably based on the type of infection and patients’ health, including other medications they may be taking.
“We’re trying to find the sweet spot,” she says. “We’re trying to find the shortest length of therapy that clears the infection without recurrence.”
Studies have found that shorter courses of antibiotics are as effective as longer ones in treating skin infections, pneumonia and uncomplicated urinary tract infections.
But one recent study looking at children under 2 with middle-ear infections found that those treated with the standard 10-day course did better than those with a five-day course.
“I’m reluctant to say for every patient that it’s OK to just stop taking your antibiotics when you feel better,” Dr Hicks says. But, she noted, “there are probably a lot of opportunities for patients who have mild infections and for which there isn’t a well-established duration of therapy to take a watch-and-see approach.”
Vance Fowler, a professor of medicine in the division of infectious diseases at Duke University Medical Center, says there are circumstances in which he abbreviates therapy, making sure the patient is aware of signs of relapse. “If you can partner with your provider in terms of watching out for adverse events, then it actually is something that makes a lot of sense,” he says.
Dr Fowler heads the federally funded Antibacterial Resistance Leadership Group. This network of nearly 100 researchers worldwide is conducting about 35 studies on antibacterial resistance, such as comparing five and 10 days of treatment for paediatric pneumonia.
The theory, he says, is that the longer antibiotics are used, the more likely the bacteria or organisms can develop ways of resisting them. “And it’s important to point out that the resistance that develops may not be in only the bacteria that you’re treating,” he says, noting that humans carry pounds of bacteria, both good and bad. “All or most of those bacteria will be exposed to the antibiotics.”
Barbara E. Murray, director of the division of infectious diseases at the University of Texas Health Science Center in Houston, says most trials focused on duration were based on trial and error.
She cautioned that it can be hard for a patient to truly know when they are better. For example, coughs in some infections can persist for long after the bacteria have been killed. Conversely, patients may feel better on antibiotics while still having an active infection.
And some conditions, like heart-valve and bone infections, require taking antibiotics for extended periods. “There a patient may feel better after a week, but if they stop taking antibiotics, then they will relapse,” she says.”
The Wall Street Journal