Potential drug-drug interactions with psychotropic drugs in paediatric inpatients: A cross-sectional study

Polypharmacy and drug-drug interactions (DDIs) are important problems that necessitate more attention in paediatric inpatients. This study aimed to determine and evaluate DDIs in paediatric inpatients using psychotropic drugs.

It was conducted as a retrospective cross-sectional study. Inpatients consulted by child and adolescent psychiatrists (CAPs) and had at least one psychotropic drug-using between January 2016 and September 2017 were retrospectively included. To determine the clinical significance of DDIs by Micromedex^® and DDI Predictor online databases. DDIs between psychotropic and other drugs, the type, severity, and duration of potential DDIs were evaluated.

During the study period, 564 patients' records were reviewed and 200 patients were considered eligible and included in the study. The median (min-max) age was 13.70 (1.5-17.83) years. The mean (SD) number of psychotropics used during hospitalisation was 1.29 (0.55) and the total number of drugs was 7.39 (4.45). A total of 336 potential DDIs were detected (2.19 DDIs/patient) in all patients. The most common potential outcome of psychotropic DDIs was drug-induced QTc prolongation (67.56%). While 92.85% of the potential DDIs were "contraindicated" or "major," only 18.46% had a "good" or "excellent" strength of evidence. The risk of psychotropic polypharmacy (OR:0.73, 95% CI 0.59-0.92; p:0.006) and DDIs (OR:0.69, 95% CI 0.35-0.76; p:0.033) was significantly higher in patients without primary psychiatric disorders. When the total number of drugs and the total number of potential DDIs were compared amongst all inpatient units, significant differences were found between paediatric hematology-general paediatrics (mean difference: 2.002; P < .001) and paediatric hematology-paediatric ICU (mean difference: 1.650; P = .012), respectively.

Psychotropic drug-related DDI is a major problem in the paediatric population and the clinical significance of the potential DDIs' risk should be determined in patient-centred care and managed by the multidisciplinary team.