Antibiotics are among the most commonly prescribed medications in both outpatient and hospital settings. Global efforts at curbing antibiotic-resistant strains have prompted clinicians to pursue better stewardship, whereby they limit their prescribing of such medications to those who truly need them.
Yet there’s another possible means of addressing antibiotic resistance – using dietary interventions to reduce the gastrointestinal complaints that so often accompany the use of antibiotics: vomiting, nausea, diarrhea, bloating/indigestion, abdominal pain, and loss of appetite. Far from being a mere nuisance, these complications can have major ramifications.
“Often [these side effects] will result in people stopping an antibiotic they need or taking a second- or third-generation one, which potentially causes even more problems with resistance,” explained Daniel J. Merenstein, MD, a professor of family medicine at Georgetown University, Washington, who has conducted multiple trials on antibiotic stewardship and probiotics.
And it’s not just clinicians who would like to find a way around these common complaints. On lifestyle blogs such as Livestrong and Goop, medical news websites, and via academic institutions, patients can learn how the right probiotic supplement or certain fermented or high-fiber foods, for example, might spare them the upset stomach that often accompanies a course of antibiotics.
Yet according to experts in the field, there are notable questions to be answered about whether there’s evidence to support this approach.
The cost of GI discomfort
Pinpointing the exact manner by which antibiotics upend GI tracts is a complex task, according to Gail Cresci, PhD, RD, a microbiome researcher in the department of pediatric gastroenterology, hepatology, and nutrition and director of nutrition research at the Cleveland Clinic.
“A lot of different mechanisms can go awry,” Dr. Cresci said. “But normally, the good microbes are there to help keep the balance, so when that balance is gone, the pathogens can take over and lead to this disruption.”
According to Lynne V. McFarland, PhD, a recently retired infectious disease epidemiologist who now serves as a private consultant, such complications can have substantial ramifications for patients and health care systems.
“If you’re an inpatient and develop antibiotic-associated diarrhea, it usually increases the length of stay from 8 to 20 days. It also increases the cost of care. And small children who have this can get severely dehydrated, which can become life threatening.”
Proponents of probiotics
Several of the researchers who were interviewed believe there’s convincing evidence supporting probiotics for the treatment of common antibiotic-related GI complaints. In many instances, they were involved in the studies themselves.
During Dr. McFarland’s 4-decade career in probiotics research, she has participated in early animal studies with strains such as Saccharomyces boulardii and was involved in meta-analyses of their role in Clostridioides difficile infection and associated diarrhea and even as a potential GI intervention for COVID-19 patients (Antibiotics (Basel). 2021 Apr 9;10(4):408).
In mouse model studies from 2013 and 2018, Dr. Cresci and colleagues showed that the probiotic strains Lactobacillus GG and Faecalibacterium prausnitzii reduced the structural gut changes that lead to antibiotic-associated diarrhea and minimized the risk of C. difficile infection.
In a 2021 randomized controlled trial led by Merenstein, healthy participants were given a trial of amoxicillin/clavulanate (days 1-7) in conjunction with either yogurt containing the probiotic Bifidobacterium animalis subsp lactis BB-12 or control yogurt (days 1-14). After assessing feces samples over a 30-day period, they found that those who received the probiotic yogurt had a significantly smaller decrease in short-chain fatty acid levels and a more stable taxonomic microbiota profile than control persons.
Dr. Merenstein said that, on the basis of results such as these and others, he’s comfortable being relatively definitive about the value of probiotics.
“I believe it’s close to standard of care that if you’re prescribing antibiotics, especially for more than 7 days, you really need to put people on probiotics that have been studied, simply because the evidence is robust enough now,” he said.