(B-110) Potential Drug Interactions among Psychotropic Medications prescribed in Hospitalized Patients at a National Hospital in Peru

Monday, August 25, 2025

11:30 AM - 1:00 PM ET

Presenting Author(s)

Alejandra Zevallos

Centro de Investigación Básicas y traslacional, Auna Ideas, Lima, Perú, Peru

Co-Author(s)

CS

Carlos Saldaña Reyes

Centro de Investigación Básicas y traslacional, Auna Ideas, Lima, Perú, Peru
JS

José Salvador Carrillo

Escuela Profesional de Medicina Humana, Universidad Privada San Juan Bautista, Filial Ica, Peru, Peru
YF

Yomali Ferreyra Chombo

Escuela Profesional de Medicina Humana, Universidad Privada San Juan Bautista, Lima, Perú, Peru
LC

Luciane Cruz Lopes, PhD

University of Sorocaba, Brazil
JH

Jeff Huarcaya-Victoria, MD

School of Medicine, San Juan Bautista Private University, Ica, Peru., Peru

Background: Drug-on-drug interactions (DDIs) are a significant concern in hospitalized patients, particularly among those receiving psychotropic medications.

Objectives: This study aimed to analyze the prevalence of DDIs among prescribed psychotropic drugs in hospitalized patients at a national hospital in Peru.

Methods: We conducted a retrospective study with the clinical records of hospitalized patients at the Guillermo Almenara Irigoyen National Hospital from 2020 to 2022. All prescriptions were analyzed using the Medscape Drug Interaction Checker (WebMD LLC), an online database which classifies interactions according to their clinical significance (Contraindicated, Serious (Use Alternative), Monitor Closely, Minor).

Results: A total of 1,919 patients were evaluated, with a median age of 62 years (IQR: 47–73), and 56% (n=1074) of the population were women. Among 2,316 treatments were analyzed and 327 DDIs were identified. The most frequently prescribed combinations included sertraline-alprazolam (n=111), sertraline-clonazepam (n=106), mirtazapine-clonazepam (n=63), mirtazapine-alprazolam (n=60), and sertraline-quetiapine (n=28). While sertraline-alprazolam and sertraline-clonazepam had no reported interactions, mirtazapine-clonazepam and mirtazapine-alprazolam required close monitoring due to an increased risk of sedation. sertraline-quetiapine was classified as a serious interaction due to QTc interval prolongation, posing a risk of life-threatening arrhythmias. Overall, 14.1% (n=327) of treatments had clinically relevant interactions, with 74.9% (n=245) requiring monitoring, 23.5% (n=77) considered serious, 1.5% (n=5) posing a minor risk.

Conclusions: In our experience, the prevalence of DDIs was 14.1%. The most frequent risks identified were excessive sedation and increased QTc intervals. These findings highlight the importance of systematic prescription evaluation to minimize potential adverse effects.