Exploring the factors and outcomes of clozapine discontinuation in India: A retrospective analysis

Clozapine is used in the management of treatment-resistant schizophrenia. Although the reported adverse effects with clozapine are more, and the risk of clozapine discontinuation is present, few Indian studies have examined the correlates of clozapine discontinuation. Furthermore, there is a lack of consensus on alternative treatment after clozapine discontinuation. This study aimed to explore these factors among patients treated in a tertiary psychiatric centre in India.

We performed a retrospective chart review of the clozapine database from tertiary care schizophrenia clinic services (2015-2023) and identified 30 eligible case records of clozapine discontinuation. We examined the correlates of clozapine discontinuation.

Among patients who discontinued clozapine, 66.7 % were male, with an average age of 32.30 ± 9.78 years. The most common causes for discontinuation were adverse effects(56.67 %), inadequate therapeutic response(23.34 %), and non-adherence(13.33 %). Down-titration was used for 58.82 % (10/17 in whom discontinuation method details were available) of patients, with no withdrawal adverse effects noted. Clozapine retrial was considered among nine patients. Following clozapine discontinuation, among the interventions tried, ECT showed a significant response, followed by haloperidol and risperidone. Amisulpride, olanzapine, and flupentixol depot showed a moderate response.

These results align with previous studies, showing that adverse effects and inadequate response are prominent reasons for clozapine discontinuation and demonstrate the possibility of clozapine retrial in selected patients. Managing adverse effects might result in improvement, at least to a mild degree. Clozapine discontinuation can be avoided in a cohort with non-serious adverse effects, given the superiority of clozapine in resistant schizophrenia.