Is off-label use a risk factor for adverse drug reactions in pediatric patients? A prospective study in an Indian tertiary care hospital.

BACKGROUND: The lack of specific medicines and labeling recommendations for the pediatric population is a long-standing problem. Using data from an observational study of adverse drug reactions (ADRs) among pediatric inpatients, we aimed to test the hypothesis that off-label status is a risk factor for ADRs. METHODS: A prospective intensive surveillance was conducted at a pediatric ward of a public teaching hospital. Adverse events to labeled and off-label use were assessed for incidence, severity and predictors. A multivariate Cox proportional hazards regression model used to assess off-label use is a risk factor for ADR occurring. RESULTS: Off-label and labeled use were responsible for 34 (67%) and 17 (33%) ADRs respectively. Medicines which lacked complete pediatric labeling had the greatest odds for ADRs (9.21% of medicines in this category were implicated, OR 2.84 (95% CI 1.37-7.09). Number of off-label medicines given to patient significantly increased the hazard of an ADR (hazard ratio (HR) 1.28, 95% CI 0.43-3.78, P = 0.002). Number of medicines given also significantly increased the hazard (HR 1.2, 95% CI 0.80-1.71, P < 0.001). CONCLUSIONS: Use of off-label medicines were more likely to be implicated in an ADR than labeled medicines. This off-label use would be acceptable if evidence of potential benefits outweighs ADRs risk.