Fatal Adverse Drug Reactions: A Retrospective Forensic and Pharmacovigilance Study in DHQ Hospital Charsadda

Abstract

Background: Adverse drug reactions (ADRs) are an uncommon but important cause of death that can be prevented. More effective integration of clinical and pharmacovigilance and forensic evidence will enhance the identification of the medicine related deaths.

Objective: To determine the clinical patterns, suspected medicines, causality, preventability and forensic characteristics of fatal ADRs at DHQ Hospital Charsadda.

Methods: The study is a retrospective observational study consisting of 86 suspected fatal ADR cases between January and June 2025. The clinical files, medication charts, death records, pharmacovigilance forms, available post mortem and toxicological report were studied. The WHO–UMC system was used to assess causality, and the modified Schumock and Thornton criteria were used to assess preventability. Crude binary logistic regression was used to assess factors related to potentially preventable reactions.

Results: The mean age was 58.6 ± 16.4 years, 55.8% of patients were male and 59.3% had polypharmacy. Anticoagulants and antiplatelet medicines were the leading suspected drug class (23.3%), followed by antimicrobial agents (20.9%) and glucose-lowering medicines (14.0%). Major haemorrhage was the most frequent fatal manifestation (23.3%), followed by anaphylaxis (17.4%) and severe hypoglycaemia (12.8%). Overall, 59.3% of reactions were considered potentially preventable. Medication error (AOR = 8.14; p = 0.010), inadequate monitoring (AOR = 4.72; p = 0.018) and polypharmacy (AOR = 3.21; p = 0.026) were independently associated with preventability. Only 20.9% of cases had been formally reported to a pharmacovigilance centre.

Conclusion: A considerable proportion of suspected fatal ADRs appeared preventable. Stronger medication review, laboratory monitoring, dose adjustment and pharmacovigilance reporting may reduce medicine-related mortality.