Prevalence and Clinical Significance of Potential Drug-Drug Interactions at Ayder Referral Hospital, Northern Ethiopia

Introduction: Clinically significant drug-drug interactions reduce effectiveness of drugs or cause fatal adverse events. Although harmful drug interactions are preventable, clinicians’ recognition and detection of drug interactions is not optimal. Objective: To assess prevalence, clinical significance and factors associated with potential drug-drug interactions at medical ward of Ayder Referral Hospital, Ethiopia. Methods: A cross-sectional study was conducted to determine potential drug-drug interactions. A total of 204 patients’ medical records were analyzed for drug-drug interaction using Micromedex drug interaction software. Data were analyzed using SPSS version 16. Results: We identified 135 interacting-combinations in a total of 266 potential drug-drug interactions (pDDIs) with a mean of 1.3 pDDIs per patient. Of these, 30.1% and 53.7% of patients had at least one major and one moderate pDDIs respectively. The most common pDDIs involved were concurrent use of clarithromycin with simvastatin, aspirin with heparin and dexamethasone with rifampin which have contraindication, major and moderate severity respectively. There was significant association of occurrence of pDDIs with polypharmacy (p<0.01). Conclusion: Potential drug-drug interactions were common at the medical ward of our hospital.