Incidence of Drug-Drug Interactions among Patients Admitted to the Department of General Medicine in a Tertiary Care Hospital

Background: Drug-Drug Interactions (DDIs) contribute to increased rate of morbidity and mortality increasing the need for intense monitoring of patient safety which can be achieved by detecting and preventing morbidities associated with DDIs. Objective and Methodology: The present work was a prospective study carried out for a period of six months, to assess the incidence of DDIs in patients admitted to the Department of General Medicine at a tertiary care hospital. Results: Prescriptions of 411 patients were analysed, out of which 165 (40.15%) prescriptions were identified with potential DDIs whereas clinical manifestations of actual DDIs were observed and reported in 23 (5.6%). A total of 657 DDIs were observed of which 6 (0.9%), 240 (36.5%), 374 (56.9%) and 33 (5.6%) were of contraindicated, major, moderate and minor severity respectively. Based on the mechanism 310 (47.2%) of the identified DDIs were pharmacodynamic and 243 (36.9%) were pharmacokinetic interactions. There was a positive correlation between the number of DDIs and risk factors such as length of hospital stay, number of drugs prescribed and co-morbidities. Conclusion: This study concludes that awareness on the most prevalent DDIs can help the practitioners to prescribe drugs with a low risk for DDIs and prevent the concomitant use of dangerous drug combinations.