A study of potential drug-drug interactions among critically ill patients at a tertiary care hospital

Background: Drug interaction is said to occur when presence of one drug affects the activity of another drug when both are administered together. This action can be synergistic or antagonistic. The objective was to study the prevalence of potential drug-drug interactions (pDDI), their severity, clinical significance, and their association with patient characteristics in intensive care unit (ICU) at a tertiary care hospital.Methods: A prospective, observational study was conducted in ICU patients for a period of 3 months to assess the pDDI using Medscape drug checker software and Lexi-Comp, inc. version: 2.7.5. drug interact android mobile application.Results: A total of 183 subjects were included in the study with a prevalence of 76.50% pDDI occurring in patients, majority of which were suffering from cardiovascular conditions (26.23%). In those with hospital stay more than five days, 92% had pDDI. There were 229 potentially interacting drug pairs with corticosteroids, aspirin, beta blockers, and diuretics being commonly involved in pDDI. A total of 2336 interactions were observed with an occurrence rate of 12.76 DDI per patient. Severity was moderate in 64%, interaction mechanism was pharmacodynamic in 72.49% and risk rating category was C in 77.1% of the study population.Conclusions: The present study showed high concomitant administration of potentially interacting drugs. The prevalence confirmed the association of age and polypharmacy. Vigilant prescribing approach is needed to prevent hazardous outcomes of pDDI