Background: Drug interactions are estimated to occur between 3% and 5% in patients to whom few drugs are prescribed and 20% among those who use 10 to 20 drugs simultaneously. In critical care units (CCUs), patients are at increased risk for the development of drug interactions due to use of more medications to treat multifaceted conditions of patients. Aim: To estimate incidence and to assess the predictors involved in causing potential drug-drug interactions in patients admitted to critical care units of a tertiary care hospital at Mysuru. Methodology: It was a prospective interventional study. All the patients who satisfied the study criteria were included in the study and patients were followed till their discharge. All the required data were collected and documented. Each prescription was subjected for review in order to identify the drug - drug interactions by using the standard references such as Micromedex, Medscape and Stockleys drug interaction. The incidence was estimated. The predictors of PDDIs were determined by using logistic regression analysis. Results: Of the 500 patients, a total of 591 potential drug â drug interactions (PDDIs) were identified from 257 patients. The incidence of PDDIs was 51.4%. Anti â infectives for systemic use [n = 962] was widely used class of drugs. In most cases, Asprin (41.9%) and Furosemide (37.5%) were observed to be the index and interacting agent respectively. Age and multiple drug therapy were the predictors of PDDIs. Conclusion: The incidence of potential drug â drug interactions was high. As elderly patients and polypharmacy were observed to be predictors of PDDIs, cautious use of medicines in elderly population especially in patients receiving multiple drug therapy is warranted to prevent or minimize the PDDIs in critical care units.
