A systematic review and meta-analysis was conducted using twelve electronic databases to evaluate the evidence for probiotics in the prevention and treatment of antibiotic-associated diarrhea (AAD). Studies that used one or more species of live microorganisms of Lactobacillus species, Bifidobacterium, Saccharomyces, Streptococcus, Enterococcus and/or Bacillus were included. Randomized trials were included if the probiotics were used as prevention, treatment or concomitantly with antibiotics to enhance treatment such as is the case in Helicobacter pylori. A total of 82 randomized clinical trials met the inclusion criteria. The majority of the interventions with probiotics were primarily Lactobacillus species, either alone or in combination with other species such as Bifidobacterium, Saccharomyces boulardii or Hansen species. Very few studies had used the Enterococcus, Streptococcus or Bacillus strains.
According to this systematic review, using probiotics as an adjunct to antibiotic therapy reduced the risk of AAD with a relative risk of 0.58 (or 42%). The species predominantly used were Lactobacillus rhamnosus or Lactobacillus casei.
Commentary: These results are affirming for those who already have this habit of using a probiotic for the prevention and treatment of AAD. We should remember though that AAD does not occur in the majority of patients taking antibiotics. What would be even more useful would be a study that determined which patients might benefit more. Examples could include studying probiotics with those antibiotics that are more likely to cause diarrhea. Another approach would be to study those who are elderly or those with a previous history of this problem. Another helpful approach would be to know which species may be indeed more effective at prevention and treatment of this particular clinical problem.
Hempel S, Newberry S, Maher A, et al. Probiotics for the prevention and treatment of antibiotic-associated diarrhea. JAMA 2012;307(18):1959-1969