Is a shorter antibiotic course just as effective as a longer one?
There is growing concern in the medical community about antibiotics losing their effectiveness. Overuse of the often lifesaving drugs can cause certain bacteria to become antibiotic-resistant over time.
In response to this growing problem, the American College of Physicians has released new guidelines recommending a shorter course of antibiotics for four of the most common bacterial infections seen in inpatient and outpatient settings.
The four common infections and the new prescribing guidelines are:
- COPD and acute uncomplicated bronchitis with clinical signs of bacterial infection: Five days.
- Community-acquired pneumonia: Five days, with an extension of therapy if needed.
- Urinary tract infections in women with uncomplicated bacterial cystitis: Five days of the drug nitrofurantoin, or three days of the drug trimethoprim-sulfamethoxazole, or a single dose of Fosfomycin.
For men and women with the type of urinary tract infection known as uncomplicated pyelonephritis: five to seven days of fluoroquinolones or 14 days of trimethoprim-sulfamethoxazole.
- Cellulitis, Five-to-six-day regime of antibiotics active against streptococci.
For all four infections, longer durations should be the exception if patients aren’t responding, not the go-to rule, according to the new guidelines.
“I’ve actually been paying attention to this for the past couple of months,” said Primary Care Physician Michael Messina, MD at Bramblebush Primary Care in Falmouth. “It makes a whole lot of sense to me. It was thought that longer is better because you want to make sure you eradicate all of the bacteria, but that logic doesn’t necessarily hold."
There are a couple of reasons for the change in prescribing recommendations. Taking antibiotics for too long risks negatively affecting the gut biome – the healthy population of microorganisms in your gastrointestinal tract - and causing adverse side effects. Doctors are just starting to understand the importance of a healthy gut biome and its role in affecting autoimmune diseases and other areas of health.
“If the longer duration of an antibiotic doesn’t increase the benefit but it does increase the side effects, then you probably shouldn’t use the longer course because then the risks outweigh the benefits,” Dr. Messina said. “Where does the balance lie with treating with a proper course of antibiotics that truly eradicates the infection without having an unnecessary negative effect on the gut biome and having an unnecessary chance of increasing the risk of C-diff (C. difficile, a bacteria that causes severe diarrhea and inflammation of the colon)?”
A longer course of antibiotics also causes selective pressure by killing susceptible bacteria, allowing antibiotic-resistant bacteria to survive. That means that the next time the patient gets an infection, they could experience a drug-resistant infection that is harder to treat, he said.
Change Takes Time
“In the last few years these studies have been going on, but medical practices are slow to change,” Dr. Messina said. “It takes a little while for people to get a large enough burden of evidence from enough studies showing the same conclusion to convince people to change what they are doing.”
These new guidelines will help change both medical practice and patient acceptance, he said. While some patients are thrilled to take fewer pills, others are wary of straying from the norm. For those patients, Dr. Messina can now point to the guidelines to support prescribing a shorter dose.
“I think it’s going to be a positive change overall,” he said. “Medicine is both an art and a science. We shouldn’t rest on our laurels. We should continue to investigate to make sure we are doing the right thing, and when we find out we haven’t been doing things the right way, let’s change our practice.”
Drug-resistant bacteria are a genuine threat because there are no new antibiotics in the pipeline right now. No new families of drugs are being invented, so we need to be good stewards of the ones we have. That means using the narrowest spectrum antibiotic that will get the job done for the shortest duration, Dr. Messina said.
“That’s how we can prolong the effectiveness of the antibiotics that we have now,” he said. “Nobody wants to be in a post-antibiotic era and we are starting to see urinary infections in certain parts of the world that are resistant to everything we’ve got.”
Nursing homes and assisted living facilities have added to the strain on antibiotics. Nurses are trained to request a urine test if a resident has a change in mental status. This can be a disservice because while one-third of the changes in mental status are due to a urinary tract infection, two-thirds are not, Dr. Messina said. When nurses call him about ordering tests, he always asks if the patient has other symptoms, such as newly-developed incontinence, burning during urination, urinating more frequently or pain in the bladder region.
In the absence of urinary symptoms, he looks for other reasons for the change in mental status. The problem with testing every resident is that colonization of bacteria in the urine is common in skilled nursing facilities, but colonization by itself is not a problem.
“There is ample evidence going back a couple of decades that treating bacteria in the urine with no symptoms provides zero benefit for the patient and puts the patient at risk for harm of antibiotic side effects,” Dr. Messina said. “It puts society at risk of harm from drug-resistant bacteria. That’s actually one of the major drivers of drug-resistant bacteria in the healthcare system as a whole. So doing that is actually bad medical practice because I’m not benefiting anybody and I could be hurting somebody.”
Dr. Messina believes strongly that doctors should question their assumptions and if they find their assumptions are wrong, they need to change their practices. Before he orders any tests, he asks himself two questions:
- What information am I looking for with this test?
- How is this test going to change how I treat this patient?
“If I can’t answer both questions, then I shouldn’t order the test,” he said.