Study: Probiotic Supplement May Prevent Antibiotic-Associated Diarrhea

Eating yogurt may protect your gut while you’re on antibiotics treatments. A new study published in Nutrients found that a particular probiotic strain may reduce the negative effects of antibiotics on the gut microbiome.

About one in five people who take antibiotics develop antibiotic-associated diarrhea (AAD) because the drugs disrupt the healthy gut microbiome, according to the study. Researchers found that the probiotic strain Bifidobacterium animalis subspecies lactis BB-12 (“BB-12”) may protect against AAD.

Although side effects from antibiotics are fairly common, they could be unpleasant and at times severe.

“A lot of people will get diarrhea with cramping and will stop the antibiotic early, so that can cause problems,” Daniel Merenstein, MD, professor of family medicine and director of family medicine research at Georgetown University and one of the study authors, tells Verywell. “Sometimes they’ll switch to another antibiotic, which is even stronger which causes more resistance.”

Patients who quit their antibiotics course early may still be sick from the original infection, and they might end up having to restart a new course completely.

In very rare cases, patients who stay on antibiotics for a long period can develop Clostridioides difficile (C. diff) diarrhea. Merenstein says that C. diff infection is potentially dangerous because the patients may experience even worse gastrointestinal symptoms that could lead to hospitalizations.

In order to prevent AAD and improve tolerance with antibiotic-related side effects, researchers looked at probiotics as a way to reduce these discomforts.

For this study, 42 participants received a seven-day course of antibiotics along with a probiotic yogurt supplemented with BB-12 while 20 other participants were given a placebo.

Researchers then measured changes in the levels of short-chain fatty acid (SCFA), which are produced by healthy gut bacteria. While antibiotics work by killing off bacteria, they can significantly reduce the good bacteria in the process and affect gut health.

The results showed that the participants who ate yogurt with BB-12 had a more stable gut microbiome and SCFA levels than the placebo group. This means that probiotics taken with antibiotics may help cut down on AAD and antibiotic non-compliance.

Potential Benefits of Probiotics

Arjun Avila, a product development consultant specialized in vitamins and probiotic supplements, says probiotics are essentially “very tiny living microorganisms” and there are thousands of probiotic strains that offer different health benefits.

“Probiotic strains are diverse,” Avila says. “If you think of dog breeds, it can range from chihuahua to pit bulls, and probiotic strains are very much like that as well.”

Researchers are still studying these various probiotic strains to understand exactly how they work. But some studies have shown that probiotics may help improve heart health and support digestive systems, especially when the levels of healthy gut bacteria are off balance.

“Probiotics are able to help you balance your gut so that you don’t have as many unwanted side effects from the use of antibiotics,” Avila says.

Probiotics can be found in yogurt, as well as a wide range of fermented foods like kimchi, miso, kombucha, and kefir. It’s generally best to obtain probiotics from food sources since they also offer other nutrients. But probiotic supplements are convenient and easy to travel with, Merenstein adds, and they can last longer than many probiotic foods that need to be refrigerated.

Merenstein also stresses the importance of taking the probiotics as early as possible, before any antibiotic symptoms emerge. In the study, participants started the probiotics regimen the same day they started taking the antibiotics.

In an earlier study published in Cell, participants were only given probiotics a week after starting the antibiotics. The results instead showed that the probiotics delayed the return of the gut microbiome to homeostasis.

Probiotics Research Is Still New

While the new study offers promising results, it was conducted on a small sample size of only 62 participants. Additionally, there’s still a lot that scientists don’t know about probiotics.

“The topic is still really new,” Avila says, adding that it may be trial-and-error process to figure out which probiotics work best for individuals by cycling through different supplement brands.

As studies with positive results continue to be published, more funding may be funneled into probiotics research. For instance, the National Institutes of Health has already backed a follow-up study.

“I’m very hopeful for the future of probiotics,” Avila says. “In the marketplace right now, there are probiotics that help with healthy-looking skin and probiotics that help with levels of cholesterol levels. There are so many applications for probiotics that we are just starting to find out about.”