{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,20]],"date-time":"2026-08-20T14:32:24Z","timestamp":1787236344207,"version":"build-2736575974"},"reference-count":22,"publisher":"BMJ","issue":"8","content-domain":{"domain":["bmj.com"],"crossmark-restriction":true},"short-container-title":["BMJ Case Rep"],"accepted":{"date-parts":[[2026,8,6]]},"published-print":{"date-parts":[[2026,8]]},"abstract":"<jats:p>We highlight a case of zuclopenthixol-induced neutropenia, a rarely reported adverse effect (AE), and subsequent susceptibility to clozapine-induced neutropenia. Neutropenia is an uncommon but clinically significant haematological AE associated with several psychotropic agents, most notably clozapine.<\/jats:p>\n                  <jats:p>We describe a man in his 30s with treatment-resistant schizophrenia who developed medication-induced neutropenia during treatment with both zuclopenthixol and clozapine. Baseline absolute neutrophil count (ANC) was normal (3.16\u00d710\u2079\/L). During oral zuclopenthixol therapy, the patient developed neutropenia (1.29\u00d710\u2079\/L) and eosinophilia. ANC normalised following drug discontinuation.<\/jats:p>\n                  <jats:p>Clozapine was subsequently initiated with a cautious titration; however, neutropenia reoccurred (1.31\u00d710\u2079\/L), with a persistently reduced ANC for 15 days after cessation. Investigations excluded infective, autoimmune, nutritional and primary haematological causes.<\/jats:p>\n                  <jats:p>The patient was subsequently established on amisulpride and lithium, with recovery of ANC. This case highlights the potential susceptibility to antipsychotic-induced neutropenia and the consideration of lithium for augmentation of ANC in future therapy.<\/jats:p>","DOI":"10.1136\/bcr-2026-273057","type":"journal-article","created":{"date-parts":[[2026,8,20]],"date-time":"2026-08-20T13:25:16Z","timestamp":1787232316000},"page":"e273057","update-policy":"https:\/\/doi.org\/10.1136\/crossmarkpolicy","source":"Crossref","is-referenced-by-count":0,"title":["Zuclopenthixol and clozapine-induced neutropenia"],"prefix":"10.1136","volume":"19","author":[{"ORCID":"https:\/\/orcid.org\/0009-0002-8960-040X","authenticated-orcid":false,"given":"Charlie","family":"Price","sequence":"first","affiliation":[{"name":"Calderdale and Huddersfield NHS Foundation Trust, Huddersfield, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Aisling","family":"Reid","sequence":"additional","affiliation":[{"name":"Calderdale and Huddersfield NHS Foundation Trust, Huddersfield, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bhaskar","family":"Prabhu","sequence":"additional","affiliation":[{"name":"South West Yorkshire Partnership NHS Foundation Trust, Dewsbury, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"239","published-online":{"date-parts":[[2026,8,20]]},"reference":[{"key":"2026082006251036000_19.8.e273057.1","doi-asserted-by":"crossref","DOI":"10.1097\/HS9.0000000000000872","article-title":"The European Guidelines on Diagnosis and Management of Neutropenia in Adults and Children: A Consensus Between the European Hematology Association and the EuNet-INNOCHRON COST Action","volume":"7","author":"Fioredda","year":"2023","journal-title":"Hemasphere"},{"key":"2026082006251036000_19.8.e273057.2","doi-asserted-by":"crossref","first-page":"1191","DOI":"10.2174\/138945006778226642","article-title":"Psychotropic medications and leukopenia","volume":"7","author":"Sedky","year":"2006","journal-title":"Curr Drug Targets"},{"key":"2026082006251036000_19.8.e273057.3","first-page":"S70","article-title":"Blood dyscrasias induced by psychotropic drugs","volume":"37 Suppl 1","author":"St\u00fcbner","year":"2004","journal-title":"Pharmacopsychiatry"},{"key":"2026082006251036000_19.8.e273057.4","doi-asserted-by":"crossref","DOI":"10.1017\/S204579602200066X","article-title":"Clozapine haematological monitoring for neutropenia: a global perspective","volume":"31","author":"Oloyede","year":"2022","journal-title":"Epidemiol Psychiatr Sci"},{"key":"2026082006251036000_19.8.e273057.5","unstructured":"Joint Formulary Committee . 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