Analysis of Adverse Drug Reactions caused by antipsychotic drugs in a Mexican health institute

Introduction: Adverse Drug Reactions (ADR) are unwanted clinical or laboratory manifestations that are related to drug use. ADR are common and are associated with significant risk of morbidity, mortality and hospital admissions. Antipsychotics have a reduced therapeutic window, and have been related to the manifestation of a variety of ADR. Objective: To evaluate the pattern of ADRs due to antipsychotic drugs detected in patients treated at the Instituto Nacional de Psiquiatría Ramón de la Fuente Muñiz between December 2021 and May 2022. Methods: Observational, descriptive, prospective and cross-sectional study of a series of cases. The seriousness, severity, and quality of the information in the notification of the ADR were defined in accordance with NOM-220-SSA1-2016, Installation and Operation of Pharmacovigilance, while causality was determined using the Naranjo algorithm. Results: The incidence of ADRs was 59%, with one or more ADR detected in 52 of the 88 patients who were receiving antipsychotic treatment during the study period. Forty-five percent of the ADR had probable causality and 55% possible; only three ADR were classified as serious as they prolonged the hospital stay and endangered the patient's life. Conclusions: The ADR of the gastrointestinal and endocrine systems were the most incidental, with hyperprolactinemia being the most frequent. Olanzapine and clozapine were the medications that caused the most ADR. It is recommended to promote the culture of notification and follow-up of ADR caused by antipsychotic drugs.