Lactobacillus reuteri DSM 17938 for managing infant colic: protocol for an individual participant data meta-analysis.

Introduction: Infant colic, or excessive crying of unknown cause in infants less than 3 months old, is common and burdensome. Its aetiology is undetermined, and consensus on its management is still lacking. Recent studies suggest a possible link between infant colic and gut microbiota, indicating probiotics to be a promising treatment. However, only a few strains have been tested, and results from randomised controlled trials are conflicting. It is important to clarify whether probiotics are effective for treating infant colic in general, and to identify whether certain subgroups of infants with colic would benefit from particular strains of probiotics.