Your gut is a lively place. Bacteria of all kinds thrive in your intestines — and for the most part help you to thrive.
“The gut microbiota is a very complex ecosystem,” says Dr. Geoffrey Preidis, an assistant professor of pediatrics at Baylor College of Medicine and pediatric gastroenterologist at Texas Children’s Hospital in Houston. “There are many, many microbes that inhabit various niches within the intestine. Many of them work together. Many of them depend on each other.”
But sometimes, bacteria make us ill — and a doctor may recommend taking an antibiotic. “Typically antibiotics are prescribed to eliminate a pathogenic bacterium — a bacterium that’s not supposed to be there and it’s causing the person to be sick,” Preidis says. But while you’re battling strep throat or your child is getting over an ear infection, the same antibiotic that may be helping with that disrupts the ecosystem of bugs in the gut.
[See: 9 Ways to Boost Your Immune System.]
“The problem is that antibiotics have a lot of collateral damage — they don’t just target that one pathogenic bacterium that they are prescribed to eliminate. They will also target and kill off really a large portion of the otherwise normal gut microbiota that we all have within us,” Preidis says. “One of the big complications to antibiotic use is something called antibiotic-associated diarrhea, and we think it’s basically caused by disturbing the good bacteria that live inside of us.” He notes that research puts the incidence of AAD at somewhere between 2 and 20 percent for individuals taking antibiotics.
What Are Probiotics?
To encourage growth of good bacteria when taking antibiotics, many clinicians and dietitians now recommend probiotics — live microorganisms thought to confer some health benefit to the host; that is, you or whomever ingests them. The term is broadly used today to describe various strains of bacteria as well as yeast.
“There is some evidence that it helps with preventing diarrhea associated with antibiotic use,” says Dr. John Cullen, president-elect of the American Academy of Family Physicians and a family physician in private practice in Valdez, Alaska.
One bug of particular concern after antibiotic use is Clostridium difficile, which can cause diarrhea as well as more severe symptoms, like inflammation of the colon that can be life-threatening. “We tend to consider Clostridium difficile as an opportunist — when there is a disruption of the microbiota that typically inhabit a healthy intestine, that creates an opportunity for Clostridium difficile to expand its population,” Preidis says.
Difficult to eradicate, C-diff sometimes afflicts people in long-term and acute health care settings. “It’s more common in people that are in the hospital,” Preidis says. “But it can certainly happen to otherwise healthy people just taking an antibiotic that’s been prescribed for a fairly seemingly benign condition.”
Some research indicates that probiotics could help in preventing C-diff in people taking antibiotics, as well as AAD. “There is moderate evidence that probiotics can reduce the incidence of developing antibiotic-associated diarrhea, and possibly reduce the incidence of developing Clostridium difficile as well in otherwise healthy people taking antibiotics on an outpatient basis,” Preidis says. “The evidence for prevention of C. difficile is not as clear,” Cullen adds. But he still recommends probiotics for otherwise healthy patients taking antibiotics.
Probiotics come in food products, and in supplement form — everything from capsules to powders that can be added to food and drink. “Yogurt and kefir milk and sauerkraut and kimchi and all of these fermented foods or probiotic-rich foods are important to have in our diet on an everyday basis,” says Jennifer McDaniel, a registered dietitian nutritionist based in St. Louis and spokeswoman for the Academy of Nutrition and Dietetics. But when taking a probiotic to offset the potential negative effects of taking an antibiotic on the gut microbiota, she recommends taking it in supplement form.
[See: 10 Questions Doctors Wish Their Patients Would Ask.]
Because you want bacteria to take up residence, it’s best to have many, many of what are called colony-forming units, or CFUs; McDaniel generally recommends taking a probiotic supplement containing at least 5 billion CFUs per dose. “Most of the research shows that you need at least 5 to 10 billion of that bacteria that you’re taking to be most effective,” she notes. The research looking at the amounts has primarily been done in kids, but for adults: “we would be looking for those numbers or maybe even a little higher,” she says. McDaniel adds that it’s key to follow the instructions on the supplement (like refrigerating it, if that’s called for) to keep the bacteria or yeast viable.
Experts say it’s important to be choosy about the strain of probiotic, too. “We want to make sure that you’re taking the right type of bacteria with your antibiotic,” McDaniel says.
“I would not be able to recommend anything unless you tell me the condition, the age of the patient, for how long he or she’s sick [and] what all has been done,” says Dr. Pinaki Panigrahi, a professor of epidemiology and pediatrics in the College of Public Health at the University of Nebraska Medical Center, who has studied probiotics for two decades. “It is inappropriate to use one probiotic for every possible condition.”
A couple probiotics that are commonly recommended are the bacteria Lactobacillus rhamnosus GG, or LGG, and Saccharomyces boulardii. “The evidence right now doesn’t suggest that these are the very best — that these are going to have a stronger effect than other strains,” Preidis says. “We simply have the most evidence that suggests … these two strains do promote a beneficial effect.”
The Best Time to Take Probiotics
Though they’re often paired, experts typically advise against taking antibiotics with probiotics — that is, taking probiotics and antibiotics at the exact same time — to try to reduce the introduced bacteria killed by the antibiotic. So if a person is taking an antibiotic in the morning and at night, Cullen recommends having the probiotic at lunch. But just as there’s isn’t agreement on how to get your probiotics while taking antibiotics, there are no accepted guidelines for when to take probiotics. (Generally speaking, a catch 22 with trying to colonize the gut with new bacteria using probiotics while taking antibiotics is that antibiotics tend to kill off those new bacteria as well, Panigrahi notes.) Clinicians and dietitians typically say that probiotics should be taken until at least a week or two after the course of antibiotics is completed, since medicines continue to affect the gut microbiota after they’re stopped.
However, much remains unclear, including which probiotic sources are most effective. Panigrahi — who recommends probiotic supplements rather than food sources for those trying to offset the effects of antibiotics — says there simply isn’t clinical data to support recommending a specific supplement. “I would use, during or after — immediately after — antibiotic therapy, some strains that your physician has used in you,” he says. Because of limited data, Preidis and Cullen suggest that patients simply get probiotics in their diet when taking antibiotics rather than recommending supplements. (Experts typically agree that food sources, not supplements, are the optimal way to take in probiotics on an ongoing, or long-term, basis.)
Because supplements aren’t tightly regulated like pharmaceuticals, what’s in a particular supplement may be different from what’s advertised. For that reason, to be sure what’s listed on the label is in the supplement, McDaniel recommends clients buy supplements from larger, well-respected brands.
Clinicians say though probiotics in food and supplement form have generally been found to be safe, it’s important to talk with a doctor before taking any with prescribed antibiotics. “Probiotics have a very good safety profile. Some minor side effects that have been reported are thirst, constipation, bloating, flatulence, nausea, vomiting, abdominal pain, rash, and diarrhea,” the Academy of Nutrition and Dietetics notes. More serious complications like sepsis, a potentially life-threatening complication of an infection, are extremely rare. “Most cases of invasive infections associated with probiotic use have occurred in patients with intravenous catheters, elderly people, and immunocompromised populations,” according to the academy. Adults and parents of kids with health concerns should voice those to a physician in advance.
[See: 8 Questions to Ask Your Pharmacist.]
At present, experts say while probiotics show promise for people who take antibiotics — like for preventing AAD — more research is needed to translate the evolving understanding of their effect into precise advice for patients. “The evidence of that effect is still considered moderate,” Preidis reiterates, “and not strong enough yet to make some really specific clinical recommendations.”
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Getting Your Probiotic Fix When Taking Antibiotics originally appeared on usnews.com
