ArticleAnnals of general psychiatry2015
Sex differences in plasma clozapine and norclozapine concentrations in clinical practice and in relation to body mass index and plasma glucose concentrations: a retrospective survey.
Article in Annals of general psychiatry, 2015. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 20 papers, 2 of them syntheses that pooled it.
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Who cites it
20 citing papers in PubMed, 2 syntheses or guidelines pooled it, 56 citations in OpenAlex.
- A systematic review and meta-analysis of the association between clozapine and norclozapine serum levels and peripheral adverse drug reactions.Psychopharmacology · 2021Pooled it
- Population Pharmacokinetics of Clozapine: A Systematic Review.BioMed research international · 2020Pooled it
- The association of schizophrenia polygenic scores with continuously-hospitalized, treatment-resistant schizophrenia.Molecular psychiatry · 2026Article
- Safety profile of olanzapine/samidorphan: focus on metabolic risks, opioid-related effects, and novel adverse events identified.Naunyn-Schmiedeberg's archives of pharmacology · 2026Article
- Immunoinflammatory features and cognitive function in treatment-resistant schizophrenia: unraveling distinct patterns in clozapine-resistant patients.European archives of psychiatry and clinical neuroscience · 2025Article
- Following the Action of Atypical Antipsychotic Clozapine and Possible Prediction of Treatment Response in Schizophrenia.Life (Basel, Switzerland) · 2025Review
- Differences in clozapine metabolism across geographical regions in Turkiye.Dusunen adam : Bakirkoy Ruh ve Sinir Hastaliklari Hastanesi yayin organi · 2025Article
- Impacts of sex differences on optogenetic, chemogenetic, and calcium-imaging tools.Current opinion in neurobiology · 2024Review
- Weight change following diagnosis with psychosis: a retrospective cohort study in Greater Manchester, UK.Annals of general psychiatry · 2024Article
- Body mass index as a predictor of the outcomes of acute clozapine toxicity: a cross-sectional study.Toxicology research · 2023Article
- Second to none: rationale, timing, and clinical management of clozapine use in schizophrenia.Therapeutic advances in psychopharmacology · 2023Review
- Adverse Drug Reactions in Relation to Clozapine Plasma Levels: A Systematic Review.Pharmaceuticals (Basel, Switzerland) · 2022Review
- Reasons for admission to a general medical hospital for patients taking clozapine.Therapeutic advances in psychopharmacology · 2022Article
- Gender Differences in the Psychopharmacological Treatment of Forensic In-Patients With Schizophrenia.Frontiers in psychiatry · 2022Article
- Targeting muscarinic receptors to treat schizophrenia.Behavioural brain research · 2021Review
- Association of clozapine-related metabolic disturbances with CYP3A4 expression in patients with schizophrenia.Scientific reports · 2020Article
- Clozapine: An Updated Overview of Pharmacogenetic Biomarkers, Risks, and Safety-Particularities in the Context of COVID-19.Brain sciences · 2020Review
- Relationship between Clozapine-Induced Electroencephalogram Abnormalities and Serum Concentration of Clozapine in Japanese Patients with Treatment-Resistant Schizophrenia.Psychiatry investigation · 2018Article
- An Exploratory Survey of Incorporation of Gender- and Sex-related Differences in the PharmD Curricula.Innovations in pharmacy · 2018Article
- Genetic Determinants of Clozapine-Induced Metabolic Side Effects.Canadian journal of psychiatry. Revue canadienne de psychiatrie · 2017Article
Corrections and comments
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Authors and funding
8 authors at 7 institutions in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
backgroundClozapine is widely prescribed and, although effective, can cause weight gain and dysglycemia. The dysmetabolic effects of clozapine are thought to be more prevalent in women with this gender on average attaining 17 % higher plasma clozapine concentrations than men.
methodsWe investigated the relationship between dose, body mass index (BMI), plasma glucose concentration, and plasma clozapine and N-desmethylclozapine (norclozapine) concentrations in 100 individuals with a severe enduring mental illness.
resultsMean (10th/90th percentile) plasma clozapine concentrations were higher for women [0.49 (0.27-0.79) mg/L] compared with men [0.44 (0.26-0.70) mg/L] (F = 2.2; p = 0.035). There was no significant gender difference in the prescribed clozapine dose. BMI was significantly higher in women [mean (95 % CI) = 34.5 (26.0-45.3)] for females compared with 32.5 (25.2-41.0) for males. Overall, BMI increased by 0.7 kg/m(2) over a mean follow-up period of 210 days. A lower proportion, 41 % of women had a fasting blood glucose ≤6.0 mmol/L (<6.0 mmol/L is defined by the International Diabetes Federation as normal glucose handling), compared with 88 % of men (χ (2) = 18.6, p < 0.0001).
conclusionsWe have shown that mean BMI and blood glucose concentrations are higher in women prescribed clozapine than in men. Women also tended to attain higher plasma clozapine concentrations than men. The higher BMI and blood glucose in women may relate to higher tissue exposure to clozapine, as a consequence of sex differences in drug metabolism.
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Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.