Educational only — not medical advice. If you’re in crisis or thinking about suicide: call or text 988 (U.S.) or your local emergency number. Support resources. Under construction and review—see the updates log.
Brand: CLOZARIL
Published 2026-02-16 · Last reviewed 2026-02-23 · 11 references
Content sourced from FDA labeling (DailyMed) and peer-reviewed literature.
Clozapine (brand Clozaril, owned by Novartis/Sandoz) is a second-generation antipsychotic (SGA). Clozaril refers to the oral tablet; two additional branded formulations—FazaClo (an orally disintegrating tablet, or ODT) and Versacloz (an oral suspension)—support patients who cannot swallow standard tablets.
ODTs dissolve on the tongue without water, which aids adherence when swallowing is difficult. Oral suspensions are liquid formulations measured with an oral syringe so clinicians can titrate doses with finer precision.
In 1989 the FDA approved clozapine for treatment-resistant schizophrenia (TRS) or for intolerable motor side effects with other antipsychotics. TRS typically means two adequate antipsychotic trials have not delivered meaningful symptom reduction, and clozapine remains the only antipsychotic specifically approved for this population.
Early agranulocytosis reports—most notably eight Finnish deaths in 1975—delayed U.S. adoption and led to mandatory blood monitoring when clozapine launched. Effective June 2025 the FDA discontinued the U.S. clozapine REMS program, so ANC monitoring is now clinician-guided rather than tied to a dispensing registry, though vigilance for neutropenia is still prudent.
Clozapine gained a 2002 indication to reduce recurrent suicidal behavior in schizophrenia or schizoaffective disorder and is recommended in APA guidelines when persistent aggression or suicidality endures despite other antipsychotics.
A 2025 Finland/Sweden register study found clozapine use was associated with lower psychiatric hospitalization versus other oral antipsychotics across schizophrenia-spectrum disorders and several affective disorders (including bipolar disorder and psychotic depression), without evidence of increased mortality; borderline personality disorder did not show benefit.
The clozapine compare view, the clozapine evidence feed, and the clozapine print page can support care discussions; the schizophrenia hub and bipolar disorder hub include related longitudinal pathways when suicidality or aggression persists.
Multiple manufacturers (Teva, Hikma, Sun, Aurobindo, Accord, Apotex, Mylan/Viatris, among others) supply generic tablets and ODTs; Versacloz 50 mg/mL oral suspension remains brand-only in the United States.
Tablets ship in 12.5, 25, 50, 100, and 200 mg strengths; FazaClo ODTs are 12.5, 25, 100, 150, and 200 mg; Versacloz provides 50 mg/mL in 120 mL bottles. No long-acting injectable formulation exists—patients needing depot support must transition to an LAI antipsychotic.
Despite unmatched efficacy for treatment-resistant schizophrenia and suicidality, clozapine use remains modest—roughly 5–6% of U.S. outpatient antipsychotic prescriptions in 2023—because of historical REMS logistics, close follow-up requirements, and side effects such as sialorrhea. Utilization is higher in specialty early-psychosis and clozapine clinics, and many experts advocate considering clozapine earlier rather than waiting for two failed antipsychotic trials.
View labelExactRefer to the Glossary entry on Neurotransmitters for background on receptor systems involved in serious mental illness.
Clozapine displays broad receptor activity that stabilizes dopamine and serotonin signalling while moderating histaminergic, adrenergic, and muscarinic pathways.
Low-to-moderate D2 antagonism with higher D4 affinity and rapid dissociation reduces extrapyramidal symptoms; potent 5-HT2A/5-HT2C antagonism and 5-HT1A partial agonism modulate dopamine release and mood, while α1 and H1 antagonism explain orthostasis and sedation and muscarinic blockade drives anticholinergic effects.
Sources: FDA/DailyMed labeling; consensus monitoring schedules.