Minimizing the damage

Antibiotics can help you clear an infection, but they sometimes wreak havoc by killing beneficial intestinal bacteria in the process. Probiotic supplements aim to minimize the damage by providing friendly bacteria or yeasts to replace what is lost during antibiotic treatment and to prevent colonization by harmful microbes.

The new review and meta-analysis included data from 82 studies in which people receiving courses of antibiotics for a wide range of infections were also treated with probiotics. Most of the studies used lactobacillus species, alone or in combination with other bacteria, but several used a beneficial yeast called Saccharomyces boulardii.

Probiotics make antibiotics more tolerable

When the researchers analyzed the combined data, they found the following:

• People taking a probiotic supplement were 42% less likely to develop antibiotic-associated diarrhea compared to people using no supplement or placebo.
• The various strains of bacteria and yeasts used in the probiotics were all similarly effective.
• Probiotics were equally helpful in children and adults.
• People benefited similarly from probiotics regardless of the nature of the original infection for which antibiotics were given.

“Our review found sufficient evidence to conclude that adjunct probiotic administration is associated with a reduced risk of antibiotic-associated diarrhea,” the study’s authors said.

Probiotics for good health

In addition to preventing antibiotic-associated diarrhea, probiotics can be helpful for a range of other conditions. Here are some other reasons to take probiotic supplements:

• Yeast infections. Probiotics are useful for preventing and treating yeast infections such as yeast vaginitis, thrush, and intestinal candidiasis.
• Irritable bowel syndrome (IBS). Probiotic supplements can reduce IBS symptoms like bloating, abdominal discomfort, and bowel irregularity.
• Inflammatory bowel disease. Both Crohn’s disease and ulcerative colitis cause changes in the intestinal wall that make it hard for healthy bacteria to thrive. Many people with these conditions benefit from supplementing with probiotics.
• Colds and flu. Supplementing with probiotics strengthens immune function and prevents all kinds of infections, even colds and flu.

(JAMA 2012;307:1959–69)