Assessment of drug-drug interactions among patients with psychiatric disorders: A clinical pharmacist-led study

BackgroundDrug-drug interaction alters the efficacy of the drugs. Early identification can reduce unintended therapeutic outcomes.ObjectiveThe main objective of the present study was to assess the drug-drug interactions among patients with psychiatric disorders.MethodologyA prospective observational study was conducted for a period of eight months. A total of 112 psychiatric inpatients were enrolled in the study. The patients were monitored regularly to identify the incidence of potential and actual drug-drug interactions. The identified interactions were analyzed for their severity by using various standard references which included published scientific articles, online databases (e.g., UpToDate) and standard textbooks.Results and DiscussionThe mean age of the study population in years was found to be 37.93 ± 12.21 standard deviation. It was observed that the incidence of potential drug-drug interactions was 66.96%. A total of 201 potential drug-drug interactions were identified from 75 patients. Based on the severity assessment of the identified interactions, 52.73% were major, 37.31% were moderate, and 19.82% were minor. About 7.46% were contraindicated drug combinations. The data on the onset of interaction revealed that 34.82% were of delayed onset and 14.92% with rapid onset and 50.24% were not specified. The drug that was responsible for the majority of the interactions in the study was found to be olanzapine.ConclusionThe study revealed a high incidence of drug-drug interaction. Drug-drug interactions most frequently encountered among psychiatric patients were found to be major in terms of severity. The study concluded on the higher event of drug-drug interactions among the patients prescribed with olanzapine.