Clozapine Can Result in Serious Gastrointestinal Complications
Clozapine is the preferred antipsychotic for treatment-resistant schizophrenia, but has significant adverse effects, including gastrointestinal hypomotility or ‘slow gut’, which may result in severe constipation, ileus, bowel obstruction, and even death. These gastrointestinal effects remain inadequately recognized.
Clozapine remains the ‘gold standard’ in treatment-resistant schizophrenia, with its superiority well established in terms of mental health outcomes, quality of life, and life expectancy . However, clozapine’s advantages come at a cost, with an array of problematic adverse effects of which clozapine-induced gastrointestinal hypomotility (CIGH) is one of the most serious, albeit one that has received scant attention until the last decade. Gastrointestinal adverse effects of clozapine are very common and include nausea, vomiting and constipation. Other troublesome unwanted effects include dry mouth and hypersalivation, which involve the autonomic nervous system. Constipation is a particularly common adverse effect that has been reported to occur in 14-60% of patients. The management of clozapine-induced constipation has been the subject of a past Drug Bulletin . Clozapine’s association with constipation could be explained by its potent anticholinergic properties. Rarely, clozapine-induced constipation has led to serious complications including ileus, bowel obstruction and necrotising colitis. A review was conducted to determine what serious gastrointestinal adverse effects have been reported in the literature and these are discussed below