Causality and avoidability of adverse drug reactions of antibiotics in hospitalized children: a cohort study

Background: Adverse drug reactions are a problem in healthcare systems worldwide. Children are more susceptible than adults, especially when exposed to specific drug classes, such as antibiotics. Objective: To assess the incidence, causality, severity, and avoidability of antibiotic-associated adverse drug reactions in hospitalized pediatric patients. Setting: Pediatric ward of a high-complexity public hospital in northeast Brazil. Methods: A prospective cohort study was conducted over six months, including children aged between 28 days and 12 years, hospitalized for more than 48 h, and receiving antibiotics. Liverpool's causality and avoidability assessment tools were used. Primary outcome measures: Incidence of adverse drug reactions, causality, severity, and avoidability, major antibiotics implicated, risk factors. Results: A total of 183 patients were followed, and 35 suspected adverse drug reactions were recorded overall incidence equal to 14.7%. Most adverse drug reactions were classified as moderate severity (76.7%), probable (57.1%) and defined (28.6%) causality, and unavoidable (66.7%). The affected organs were the gastrointestinal system (74.1%) and skin (25.9%). Major antibiotics implicated were ceftriaxone (40.7%), azithromycin (25.9%), and crystalline penicillin (11.1%). The number of antibiotics prescribed per patient during hospitalization and the length of stay were the risk factors identified. Conclusion: Causality and severity assessment indicated that most adverse drug reactions were probable and moderate. Possibly avoidable reactions occurred due to inappropriate prescribing when preventive measures were not implemented. Monitoring the use of antibiotics in children is essential to ensure the safety of these patients.