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Management of clozapine-associated neutropenia

Published online by Cambridge University Press:  03 December 2024

Sumeet Gupta Open the ORCID record for Sumeet Gupta [Opens in a new window] ,
Angela Bannon ,
Sunil Nodiyal  and
Baxi Sinha
Sumeet Gupta*
Affiliation:
Consultant psychiatrist in a community mental health team in Tees, Esk and Wear Valleys NHS Foundation Trust, Harrogate, UK. His research interests include management of affective disorder, evidence-based medicine and clinical trials of psychotropic drugs.
Angela Bannon
Affiliation:
Final-year medical student at Hull York Medical School, University of Hull, Hull, UK. She was the president of the university's Psychiatry Society (2022–2023) and is keen to pursue a career in psychiatry.
Sunil Nodiyal
Affiliation:
Has been working as a consultant psychiatrist in community rehabilitation services for Cumbria, Northumberland, Tyne and Wear NHS Foundation NHS Trust in Newcastle upon Tyne, UK, since 2005. He currently chairs the Royal College of Psychiatrists’ Faculty of Rehabilitation and Social Psychiatry. His interests are in co-production, recovery and social determinants in mental illness. He has extensive experience prescribing clozapine and depot medications for chronic psychosis.
Baxi Sinha
Affiliation:
Consultant psychiatrist in a community mental health team in Tees, Esk and Wear Valleys NHS Foundation Trust, Stockton, UK. His research interests include recruitment and retention of psychiatrists and psychopharmacology.
*
Correspondence Sumeet Gupta. Email: sumeet.gupta@nhs.net
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Summary

Clozapine is the only evidence-based intervention for treatment-resistant schizophrenia. One of the drug's most well-known and potentially fatal adverse effects is agranulocytosis (severe neutropenia). Hence, regular blood tests are an essential component of clozapine treatment. This article presents a narrative review of the history, incidence, potential aetiology and management of clozapine-associated neutropenia. It gives an overview of clozapine monitoring requirements, including those for benign ethnic neutropenia. We point to the growing body of evidence that the risk of clozapine-induced agranulocytosis is mostly confined to the first year of treatment and that the risk of fatality is considerably lower than previously assumed. Given the absence of alternative evidence-based interventions for treatment-resistant schizophrenia, we suggest that rechallenging with clozapine should be considered in most patients with clozapine-associated mild to moderate neutropenia who do not respond to other treatments. A more careful risk–benefit analysis is needed in cases of severe neutropenia (agranulocytosis).

Keywords

Clozapineadverse effectsneutropeniaagranulocytosisschizophrenia.
Type
Article
Information
BJPsych Advances , Volume 31 , Issue 2 , March 2025 , pp. 113 - 123
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Copyright
Copyright © The Author(s), 2024. Published by Cambridge University Press on behalf of Royal College of Psychiatrists

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