Proton pump inhibitors (PPIs) are medications that are very widely used, including use for children with reflux. A recent study from Sweden used national registry data in Sweden over a decade to examine clinical details for children and adolescents 17 years or younger, matched by age and propensity score into 80 870 pairs of those who initiated PPI use and those who did not. The primary analysis examined the risk of incident asthma. The cohort included 63.0% girls; of a mean [SD] age of 12.9 [4.8] years),. Children who initiated PPI use had a higher incidence rate of asthma (21.8 events per 1000 person-years) compared with non-initiators (14.0 events per 1000 person-years), with an HR of 1.57 (95% CI, 1.49-1.64). Risk of asthma was significantly increased across all age groups and was highest for infants and toddlers. The hazard ratio was highest with pantoprazole at 2.33 (95% CI, 1.30-4.18). More details of the study, published in JAMA Pediatrics, can be viewed here.