Drug-related problems were common in the hospitalised children in this study; the most frequent were dosing problems and drug choice problems; the majority of them were preventable. Polypharmacy and transferred admission (another hospital or ward) were potential risk factors. To improve prescribing practices and minimise the risk of DRPs in hospitalised children, paediatric pharmacology and pharmacotherapy are important in medical education.

A drug-related problem (DRP) is 'an event or circumstance involving drug therapy that actually or potentially interferes with the desired health outcome'. The extent and characteristics of DRPs in children in Hong Kong are unknown. The aim of this study was to determine the epidemiology of and identify risk factors for DRPs in hospitalized children in Hong Kong. METHODSThis was a prospective cohort study in children aged 0-18 years who were admitted to a medical ward, paediatric intensive care unit or neonatal intensive care unit of seven Hong Kong hospitals, during a 3 month period. Patients' charts, medical records and laboratory data were reviewed daily to identify DRPs; their preventability and severity were assessed. Logistic regression was used to analyse potential risk factors associated with the incidence of DRPs. RESULTSThree hundred and twenty-nine children (median age, 2 years; interquartile range, 0 months to 9 years) were included. In total, 82 DRPs were experienced by 69 patients. The overall incidence of DRPs was 21.0% (95% confidence interval, 16.7-25.8%). The incidence was higher in neonatal and paediatric intensive care units than medical wards. Dosing problems were the most frequently reported DRPs (n = 35; 42.7%), followed by drug choice problems (n = 19; 23.2%) and adverse drug reactions (n = 11; 13.4%). Sixty-seven (81.7%) DRP cases were assessed as preventable, 42 (51.2%) as minor and 40 (48.8%) as moderate. The number of prescribed drugs and 'certain infectious and parasitic diseases' were potential risk factors for occurrence of DRPs. CONCLUSIONSDrug-related problems were common in hospitalized children in this study in Hong Kong; the most frequent were dosing and drug choice problems, and the majority of them were preventable. Polypharmacy and 'certain infectious and parasitic diseases' were potential risk factors. WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT• The incidence of drug-related problems (DRPs) in hospitalized paediatric patients from countries other than Hong Kong is as high as 45.2%.• Dosing and drug choice problems are the most frequent DRPs in children.• There is no published research regarding the incidence and nature of DRPs in Hong Kong hospitalized children. WHAT THIS STUDY ADDS• The incidence of DRPs is as high as 21.0% (95% confidence interval, 16.7-25.8%) in children hospitalized in Hong Kong.• Of the DRPs in hospitalized children in Hong Kong, 81.7% were deemed preventable.• The number of prescribed drugs per patient (five or more) and 'certain infectious and parasitic diseases' increased the risk of occurrence of DRPs.

To reduce the risk of ADRs in children, clinicians and pharmacists should aim to minimise polypharmacy and be aware of higher ADR risks associated with some drug groups.

By comparing data from five countries in Europe, Asia and Australia we have shown that the incidence of ADRs in hospitalized children is at least as high as incidences published in adults. However, the variation between countries was mainly due to different populations and treatment strategies. Particular attention should be given to opioid use in hospitalized children.