Risperidone-Induced Agranulocytosis in a Young Patient With Schizophrenia: A Case Report
O. Seyar, L. Azizi, Z. Bencharfa, F. El OmariIntroduction
Risperidone is a widely prescribed atypical antipsychotic. Hematological adverse effects, although well documented with clozapine, are rarely associated with risperidone. We present a case of recurrent risperidone-induced agranulocytosis in a young patient with schizophrenia.
Objectives
To describe a rare case of risperidone-induced agranulocytosis in a young patient with schizophrenia, to explore its possible immuno-allergic mechanism, and to highlight the importance of hematological monitoring during antipsychotic treatment.
Methods
A 23-year-old Moroccan male with a 5-year history of schizophrenia and no relevant medical history was treated with risperidone after inadequate response to olanzapine. The dose was increased from 2 to 6 mg within four days, with good initial efficacy. Clinical monitoring and serial complete blood counts (CBC) were performed throughout treatment and rechallenge.
Results
Six weeks after risperidone initiation, progressive leukopenia and neutropenia were observed, with neutrophils falling to 750/μL after two months, leading to drug discontinuation. Chlorpromazine was also stopped, and aripiprazole (15 mg/day) was introduced, resulting in hematological recovery but poor clinical response. Risperidone rechallenge under daily CBC monitoring caused a more rapid recurrence of neutropenia within one week, supporting an immune-allergic mechanism. Alternative explanations such as ethnic neutropenia, margination, or concomitant medications (chlorpromazine, hydroxyzine) were excluded. A literature review identified 27 similar cases of risperidone- or paliperidone-induced neutropenia. This case illustrates the rare but serious risk of risperidone-induced agranulocytosis. The accelerated recurrence upon rechallenge strongly suggests hypersensitivity rather than dose-related toxicity. Although considered rare by pharmacovigilance reports, this adverse effect may lead to severe infectious complications if unrecognized.
Conclusions
Baseline and follow-up CBC monitoring should be performed after risperidone initiation, even though hematological toxicity is uncommon. The use of long-acting risperidone formulations should be delayed until tolerance to the oral form is established.
Disclosure of Interest
None Declared