Written by Hannah Harp
Spoon Feed
Antibiotic-associated diarrhea (AAD) was reported less frequently when L reuteri probiotics were taken concomitantly with amoxicillin-clavulanic acid in children with otitis or sinusitis, especially for children 2 years and younger.
When the side effects steal the spotlight
AAD (for the sake of this entry, this doesn’t include diarrhea caused by opportunistic pathogens like C diff) is a frequent complication of treating common childhood bacterial infections, thought to be due at least partially to disruption of the gut flora. While AAD itself is fairly benign, its association with the dysbiosis raises the question of whether we should attempt to supplement or replenish healthy gut flora when patients are treated with antibiotics.
This prospective, multicenter, randomized, double-blind, placebo-controlled trial evaluated whether Limosilactobacillus reuteri DSM17938 (L reuteri) prevents AAD in 654 children receiving amoxicillin-clavulanate. AAD incidence was significantly lower in the probiotic group at 14 days (7.9% vs. 16.7%, RR 0.47, p<0.001), 21 days (8.8% vs. 17.9%, RR 0.49, p<0.001), and 56 days (9.1% vs. 19.6%, RR 0.46, p<0.001). Greatest benefit was seen in children aged 6-24 months and in those with otitis media. This study has limitations; it looks at only one specific strain of L reuteri (though it is available commercially as BioGaia Protectis) and is limited to one antibiotic. Future studies should include other frequently-prescribed antibiotics, varying dosages, and different strains of probiotic. In addition, BioGaia provided the test product to the study team for free, although they had no part in the study design or how the study was carried out or analyzed.
How does this change my practice?
Diarrhea is an extremely distressing problem for parents of young children, even though it is rarely harmful. I’ve spoken to countless frantic parents living through the drama and messiness of infant and toddler diarrhea, and many of them have stopped antibiotics because the diarrhea is just too difficult to deal with. A couple of years ago, our practice started to prescribe probiotics to kids under 5, and (anecdotally) I’ve gotten fewer calls about AAD since then.
Source
Effect of Limosilactobacillus reuteri DSM17938 to prevent antibiotic-associated diarrhea in children: prospective, multi-center, randomized, placebo-controlled clinical trial (PEARL Study). Eur J Pediatr. 2025 Jun 9;184(7):408. doi: 10.1007/s00431-025-06249-8. PMID: 40488914
