Clozapine-Related Side Effects and Their Management in an Adolescent Population: A Naturalistic Observation Study in an Inpatient Clinic
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Original Article

Clozapine-Related Side Effects and Their Management in an Adolescent Population: A Naturalistic Observation Study in an Inpatient Clinic

Turk J Child Adolesc Ment Health 2025;32(2):101-109 DOI: 10.4274/tjcamh.galenos.2024.82713
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Abstract

Objectives

We aimed to evaluate the side effects seen in adolescents with clozapine use followed up in an inpatient clinic and the approaches to the treatment of side effects in a naturalistic pattern.

Materials and Methods

Sociodemographic data, International Statistical Classification of Diseases and Related Health Problems-10 diagnosis, side effects, management and outcomes, prophylactic treatments for side effects, time to initiation of clozapine and clinical observation scores were recorded.

Results

The most commonly reported side effects were extrapyramidal system side effects (n=91, 62.8%), followed by sialorrhea (n=57, 39.3%), fasciculation (n=55, 37.9%), sedation (n=43, 29.7%) and constipation (n=40, 27.4%). Of the serious side effects, seizures occurred in 5 patients (3.4%), neutropenia occurred in 5 patients (3.5%); ileus and myocarditis were not observed. The mean clozapine discharge dose was 323.9 (±124.45) mg/g. The mean number of antipsychotics used before clozapine was 3, and the mean duration from the first treatment initiation, due to a serious psychiatric diagnosis (schizophrenia, bipolar disorder), to clozapine initiation was 18.4 (±24) weeks. Valproic acid was initiated in 108 patients (74%) and topiramate in 4 patients (2.7%) for seizure prophylaxis, as seizures are one of the serious side effects of clozapine. Five patients (3.5%) developed neutropenia. The most common reason for discontinuation of clozapine treatment was non-compliance (n=8, 14%), while five patients (9.4%) were discontinued due to serious side effects or risk of these side effects.

Conclusion

In the adolescent population, it is possible to effectively intervene with different options for side effects that may affect treatment adherence due to clozapine treatment; thus preventing discontinuation of treatment and contributing to improving prognosis by reducing the time without effective symptomatic improvement.

Keywords: Clozapine, schizophrenia, bipolar

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