Clozapine: why wait to start a laxative?

Abstract

SUMMARYClozapine, the antipsychotic of choice for treatment-resistant schizophrenia, has a number of side-effects, some of which are potentially life-threatening. Historically viewed as a relatively minor side-effect, there is increasing awareness of the potentially severe sequalae of constipation secondary to clozapine-induced gastrointestinal hypomotility (CIGH). These include ileus, intestinal obstruction, bowel ischaemia, gastrointestinal necrosis, toxic megacolon and death. CIGH is significantly more common than clozapine-induced blood dyscrasias and has a higher mortality rate. Although strict criteria must be followed to assertively monitor, detect and treat blood dyscrasias in patients taking clozapine, no such framework exists for CIGH. We recommend that prescribing guidelines, regulatory agencies and information from manufacturers should more clearly highlight the risks identified in the literature. Furthermore, we recommend that, in people taking clozapine, constipation should be prevented by prophylactic treatment with laxatives rather than treated only when clinically identified.LEARNING OBJECTIVES:After reading this article you will be able to: •understand the mechanism of gastrointestinal hypomotility in those taking clozapine•improve the monitoring of clozapine-induced constipation•understand prophylactic laxative treatment and the use of less commonly prescribed laxatives in patients who experience clozapine-induced constipation.

RANZCP Abstracts

“…CIGH is a significant adverse side effect of clozapine use. Current literature has identified a role of prophylactic aperient prescribing with strict bowel monitoring, which is not as rigorously followed in clinical practice in clozapine initiation, despite the higher mortality levels associated with the progression of CIGH (Attard et al, 2019). Adverse outcomes could be avoided with more rigorous bowel monitoring and the introduction of prophylactic aperients in clozapine patients.…”

“…A common but rarely recognised side effect is clozapineinduced gastric hypomobility (CIGH). CIGH is more common than blood dyscrasias with a mortality rate of up to 18%, if undiagnosed (Attard et al, 2019;Nakamura and Nagamine, 2021). As such, it is important to distinguish the role of prophylactic aperient prescribing with clozapine use.…”

Predictors of laxative use in inpatients with schizophrenia on clozapine

“…11 Given that clozapine has the highest risk of constipation among antipsychotics 5 and might result in serious gastrointestinal complications, the latest treatment guidelines recommended a regular monitoring of bowel function and anticholinergic potential of concurrent medications as well as evaluating the risk factors of clozapine-induced hypomotility. [11][12][13] We addressed the gap in understanding of the risk factors by examining the frequency and predictors of laxative use as a proxy measure of clozapine-induced constipation.…”

Seguridad del paciente Análisis de la prescripción en adultos mayores de una policlínica de salud mental del Hospital Vilardebó, Uruguay

“…Los problemas de motilidad intestinal también son más frecuentes en personas mayores (65) . Es importante monitorear esta reacción adversa y, si es necesario, comenzar un tratamiento laxante preventivo (66) .…”