Focussing on the fundaments - assessing and treating Clozapine Induced Gastrointestinal Hypomotility

Background: Clozapine is a second-generation antipsychotic used in treatment-resistant Schizophrenia (TRS). Clozapine Induced Gastrointestinal Hypomotility (CIGH) is the commonest cause of clozapine related death, yet remains under-recognised and under-monitored.Aims and hypothesis: To review the pharmacological management of CIGH. We hypothesised that pharmacological interventions would reduce the incidence of adverse outcomes associated with CIGH.Methods: We retrospectively reviewed consecutive patients treated on clozapine over a one year period on a male acute psychiatric ward. Information on patient demographics, CIGH symptomatology, treatment and outcome were extracted.Results: In total, 14 male patients with a mean age of 43 years (standard deviation 10 years) were included. Of these, 9 patients experienced CIGH during admission, in all cases presenting as constipation. Among patients experiencing CIGH, 8 of 9 (89%) patients received one or more interventions. This was most commonly a stimulant, or osmotic laxative. By discharge, the 8 patients treated were in full remission of CIGH symptoms.Conclusions: A high proportion of patients treated with clozapine experience CIGH, presenting most commonly as constipation. Whilst potentially life-threatening, CIGH can be successfully treated in an acute inpatient setting. Active monitoring of CIGH symptoms in patients initiated, or reinitiated on clozapine is recommended.Key pointsA high proportion of patients treated with Clozapine experience constipation, the cardinal feature of Clozapine Induced Gastrointestinal Hypomotility.Whilst potentially life-threatening, CIGH can be successfully treated in an acute inpatient setting with simple interventions.Active monitoring of CIGH symptoms in patients initiated, or reinitiated on clozapine is recommended.Future research on the potential benefit of prophylactic intervention would be beneficial.