Nascimento, Diego Zapelini doMarques, Gabriela MorenoSchuelter-Trevisol, Fabiana2020-12-022021-08-042020-12-022021-08-04202021599777https://www.tandfonline.com/doi/full/10.1080/02791072.2020.1849878https://repositorio.animaeducacao.com.br/handle/ANIMA/15086Using psychiatric drugs to treat drug dependence and its comorbidities is very common. The objective of this study was to analyze the interactions between prescribed drugs for patients treated at a specialized mental health-care center for persons who use drugs, located in the state of Santa Catarina, Brazil. A cross-sectional study was conducted on secondary data collected from 2010 to 2018. We reviewed the medical records of patients aged 18 years or older who took psychotropic drugs and had any type of substance dependence. The analysis of psychotropic drug interactions was conducted in three databases: Medscape, Drug Interactions Checker, and Micromedex. We included 1,022 of the 2,322 patients attending the care center during the study period. Psychotropic drug interactions were found in 779 (76.4%) study participants, and they presented 2,292 (100%) interactions, out of which 136 (6.0%) had minor clinical risk, 537 (23.4%) had moderate risk, and 1,619 (70.6%) had major risk for the patient, totaling 172 incompatible combinations between two psychotropic drugs. Of the total number of interactions, 128 were pharmacokinetic and 44 were pharmacodynamic. The high number of psychotropic drug interactions is a serious public health issue. Psychopharmacological treatment should be carefully addressed to be safe for the patient.1-9en-USAttribution-NonCommercial-NoDerivs 3.0 BrazilDrug interactionsdrugrelated side effects and adverse reactionssubstance-related disordersmental healthpharmacovigilanceArtigo de Periodico