Adverse drug reactions and off-label drug use in paediatric outpatients

Abstract
To investigate the potential relationship between off-label drug use and increased risk of adverse drug reactions in paediatric outpatients. A prospective pharmacovigilance survey of drug prescribing in office based paediatricians was carried out in Haute-Garonne County (south west of France). The study involved a sample of 1419 children under 16 years old. Forty-two percent of patients were exposed to at least one off-label prescription. The incidence of adverse drug reactions was 1.41% (95% CI 0.79, 2.11). Off-label drug use was significantly associated with adverse drug reactions (relative risk 3.44; 95% CI 1.26, 9.38), particularly when it was due to an indication different than that defined in the Summary Product Characteristics (relative risk 4.42; 95% CI 1.60, 12.25). Our data suggest an increasing risk of adverse drug reactions related to off-label drug use. This risk would be acceptable if further studies prove the potential benefit of such a drug use.