ObjectivesEvidence is limited regarding the quality of prescribing to children. The objective of this study was to apply a set of explicit prescribing indicators to a national pharmacy claims database (Primary Care Reimbursement Service) to determine the prevalence of potentially inappropriate prescribing in children (PIPc) in primary care.Primary and secondary outcomes measuresTo determine the overall prevalence of potentially inappropriate prescribing (PIP) in children in primary care. To examine the prevalence of PIPc by gender.Design and settingCross-sectional study. Application of indicators of commission of PIP and omission of appropriate prescribing to a national prescribing database in Ireland.ParticipantsEligible children <16 years of age who were prescribed medication in 2014.ResultsOverall prevalence of PIPc by commission was 3.5% (95% CI 3.5% to 3.6%) of eligible children <16 years of age who were prescribed medication in 2014. Overall prevalence of PIPc by omission was 2.5% (95% CI 2.5% to 2.6%) which rose to 11.5% (95% CI 11.4% to 11.7%) when prescribing of spacer devices for children with asthma was included. The most common individual PIPc by commission was the prescribing of carbocisteine to children (3.3% of eligible children). The most common PIPc by omission (after excluding spacer devices) was failure to prescribe an emollient to children prescribed greater than one topical corticosteroid (54% of eligible children). PIPc by omission was significantly higher in males compared with females (relative risk (RR) 1.3; 95% CI 1.0 to 1.7) but no different for PIPc by commission (RR 1.0; 95% CI 0.7 to 1.6).ConclusionThis study shows that the overall prevalence of PIP in children is low, although results suggest room for improved adherence to asthma guidelines.