{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,7]],"date-time":"2026-10-07T13:21:05Z","timestamp":1791379265017,"version":"4.3.2"},"reference-count":15,"publisher":"MedWorks Media","issue":"2","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Psychopharmacol Bull"],"abstract":"\n Background<\/jats:title>\n Clozapine remains the most effective antipsychotic medication for treatment-resistant schizophrenia, but its use is limited by the risk of hematological side effects, particularly neutropenia. The present study aimed to determine the incidence and potential risk factors of neutropenia among patients receiving clozapine at a mental health hospital in Taif, Saudi Arabia.<\/jats:p>\n <\/jats:sec>\n \n Method<\/jats:title>\n A retrospective analytical study was conducted using electronic medical records of Saudi adult patients diagnosed with schizophrenia initiated on clozapine during one-year. Demographic and clinical data were collected, including age, gender, presence of chronic medical conditions, starting dose, and treatment duration. The absolute neutrophil count (ANC) was used as the dependent variable. Statistical analysis was performed using the chi-square test, and results with p < 0.05 were considered significant.<\/jats:p>\n <\/jats:sec>\n \n Results<\/jats:title>\n Eighty-nine patients were included (70 males and 19 females). Twenty participants (22.5%) developed neutropenia during clozapine therapy; most cases were mild. Neutropenia was less frequent among patients older than 30 years (20%) compared with younger patients (31.6%), but this difference was not statistically significant (p = 0.28). No significant associations were observed between neutropenia and gender, presence of chronic diseases, or starting dose. However, a significant relationship was found between treatment duration and the development of neutropenia (p < 0.001).<\/jats:p>\n <\/jats:sec>\n \n Conclusion<\/jats:title>\n The incidence of clozapine-induced neutropenia among patients in this Saudi sample was higher than rates reported internationally, emphasizing the need for close hematological monitoring during the first months of therapy. Awareness among psychiatrists, pharmacists, and healthcare teams should be reinforced to ensure early detection and appropriate management.<\/jats:p>\n <\/jats:sec>","DOI":"10.64719\/pb.16593","type":"journal-article","created":{"date-parts":[[2026,3,11]],"date-time":"2026-03-11T20:16:27Z","timestamp":1773260187000},"page":"122-129","source":"Crossref","is-referenced-by-count":0,"title":["Incidence and Risk Factors of Clozapine-Induced Neutropenia among Patients with Schizophrenia in Taif, Saudi Arabia"],"prefix":"10.64719","volume":"56","author":[{"given":"Ahmed Salem","family":"Altowairqi","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anas Ibn","family":"Auf","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Saeed Saeed","family":"Alghamdi","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"54175","published-online":{"date-parts":[[2026,3,9]]},"reference":[{"key":"ref1","doi-asserted-by":"crossref","unstructured":"Alvir JM, Lieberman JA, Safferman AZ, Schwimmer JL, Schaaf JA. Clozapine-induced agranulocytosis: incidence and risk factors in the United States. N Engl J Med. 1993;329(3):162\u20137.","DOI":"10.1056\/NEJM199307153290303"},{"key":"ref2","doi-asserted-by":"crossref","unstructured":"Flanagan RJ, Dunk L. Haematological toxicity of drugs used in psychiatry. Hum Psychopharmacol Clin Exp. 2008;23(S1):S27\u201341.","DOI":"10.1002\/hup.917"},{"key":"ref3","doi-asserted-by":"publisher","unstructured":"Wahlbeck K, Cheine M, Essali A, Adams C. Evidence of clozapine\u2019s effectiveness in schizophrenia: a systematic review and meta-analysis of randomized trials. Am J Psychiatry. 1999;156(7):990\u20139. doi: 10.1176\/ajp.156.7.990.","DOI":"10.1176\/ajp.156.7.990"},{"key":"ref4","doi-asserted-by":"publisher","unstructured":"Wahlbeck K, Cheine M, Essali MA. Clozapine versus typical neuroleptic medication for schizophrenia. Cochrane Database Syst Rev. 2000;(2):CD000059. doi: 10.1002\/14651858.CD000059. Update in: Cochrane Database Syst Rev. 2009 Jan 21;(1):CD000059. doi:10.1002\/14651858.CD000059.pub2.","DOI":"10.1002\/14651858.CD000059"},{"key":"ref5","doi-asserted-by":"crossref","unstructured":"Amsler HA, Teerenhovi L, Barth E, Harjula K, Vuopio P. Agranulocytosis in patients treated with clozapine: a study of the finnish epidemic. Acta Psychiatr Scand. 1977;56(2):241\u20138.","DOI":"10.1111\/j.1600-0447.1977.tb00224.x"},{"key":"ref6","doi-asserted-by":"crossref","unstructured":"Munro J, O\u2019Sullivan D, Andrews C, Arana A, Mortimer A, Kerwin R. Active monitoring of 12,760 clozapine recipients in the UK and Ireland. Br J Psychiatry. 1999;175(6):576\u201380.","DOI":"10.1192\/bjp.175.6.576"},{"key":"ref7","doi-asserted-by":"crossref","unstructured":"Kang BJ, Cho MJ, Oh JT, Lee Y, Chae BJ, Ko J. Long-term patient monitoring for clozapine-induced agranulocytosis and neutropenia in Korea. Hum Psychopharmacol Clin Exp. 2006;21(6):387\u201391.","DOI":"10.1002\/hup.779"},{"key":"ref8","doi-asserted-by":"crossref","unstructured":"Kelly DL, Kreyenbuhl J, Dixon L, Love RC, Medoff D, Conley RR. Clozapine underutilization and discontinuation in African Americans due to leucopenia. Schizophr Bull. 2007;33(5):1221\u20134.","DOI":"10.1093\/schbul\/sbl068"},{"key":"ref9","doi-asserted-by":"crossref","unstructured":"Denic S, Showqi S, Klein C, Takala M, Nagelkerke N, Agarwal MM. Prevalence, phenotype and inheritance of benign neutropenia in Arabs. BMC Hematology. 2009;9(3):1\u20137.","DOI":"10.1186\/1471-2326-9-3"},{"key":"ref10","doi-asserted-by":"crossref","unstructured":"Gerbino-Rosen G, Roofeh D, Tompkins DA et al. Hematological adverse events in clozapine-treated children and adolescents. J Am Acad Child Adolesc Psychiatry. 2005;44(10):1024\u201331.","DOI":"10.1097\/01.chi.0000171904.23947.54"},{"key":"ref11","doi-asserted-by":"crossref","unstructured":"Lahdelma L, Appelberg B. Clozapine-induced agranulocytosis in Finland, 1982\u20132007. J Clin Psychiatry. 2012;73(6):837\u201342.","DOI":"10.4088\/JCP.11m07244"},{"key":"ref12","doi-asserted-by":"publisher","unstructured":"Malik S, Lally J, Ajnakina O et al. Sodium valproate and clozapine induced neutropenia: A case control study using register data. Schizophr Res. 2018;195:267\u2013273. doi: 10.1016\/j.schres.2017.08.041..","DOI":"10.1016\/j.schres.2017.08.041"},{"key":"ref13","doi-asserted-by":"crossref","unstructured":"Lally J, MacCabe JH. Antipsychotic medication in schizophrenia: a review. Br Med Bull. 2015;114(1):169\u201379.","DOI":"10.1093\/bmb\/ldv017"},{"key":"ref14","doi-asserted-by":"crossref","unstructured":"Beck K, McCutcheon R, Bloomfield MA et al. The practical management of refractory schizophrenia: the maudsley treatment review and assessment team approach. Acta Psychiatr Scand. 2014;130(6):427\u201338.","DOI":"10.1111\/acps.12327"},{"key":"ref15","doi-asserted-by":"crossref","unstructured":"Meyer N, Gee S, Whiskey E et al. Optimizing outcomes in clozapine rechallenge following neuttropenia: a cohort analysis. J Clin Psychiatry. 2015;76:1410\u20136.","DOI":"10.4088\/JCP.14m09326"}],"container-title":["Psychopharmacology Bulletin"],"original-title":[],"deposited":{"date-parts":[[2026,10,6]],"date-time":"2026-10-06T19:36:44Z","timestamp":1791315404000},"score":1,"resource":{"primary":{"URL":"https:\/\/medworksmedia.com\/pb-article\/incidence-and-risk-factors-of-clozapine-induced-neutropenia-among-patients-with-schizophrenia-in-taif-saudi-arabia\/"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,3,9]]},"references-count":15,"journal-issue":{"issue":"2","published-online":{"date-parts":[[2026,3,9]]}},"URL":"https:\/\/doi.org\/10.64719\/pb.16593","relation":{},"ISSN":["2472-2448"],"issn-type":[{"value":"2472-2448","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,3,9]]}}}