What it's for (Indications)
- Treatment of psychiatric disorders, specifically schizophrenia, especially in patients who have responded inadequately to other antipsychotic medications or are unable to tolerate them due to severe side effects.
Dosage Information
| Type | Guideline |
|---|---|
| Standard | Initial oral dosage is 12.5 mg once daily or twice daily. If well-tolerated, increase the total daily dosage in increments of 25 mg to 50 mg per day to achieve a target dosage of 150 mg to 225 mg twice per day by the end of two weeks. Subsequently, the dosage may be increased in increments up to 100 mg once or twice weekly. The maximum daily dosage is 450 mg twice daily. Administer with or without food. Absolute Neutrophil Count (ANC) testing is mandatory prior to and during treatment, with dosage modifications based on ANC results. Consult full prescribing information for recommendations regarding discontinuing treatment, restarting after interruption, dosage modifications for drug interactions, and dosage adjustments in patients with renal or hepatic impairment or who are CYP2D6 poor metabolizers. Patients should not discontinue treatment unless advised by a healthcare professional. |
Safety & Warnings
Common Side Effects
- Common side effects include dry mouth, blurred vision, headache, dizziness, anxiety, confusion, rash, respiratory depression, and male/female sexual dysfunction.
- More severe or potentially serious adverse reactions include severe neutropenia, orthostatic hypotension, bradycardia, syncope, falls, seizures, myocarditis, pericarditis, cardiomyopathy, mitral valve incompetence, increased mortality in elderly patients with dementia-related psychosis, gastrointestinal hypomotility with severe complications, eosinophilia, QT interval prolongation, metabolic changes (hyperglycemia and diabetes mellitus, dyslipidemia, weight gain), and neuroleptic malignant syndrome.
Serious Warnings
- Black Box Warning: Clozapine carries several Black Box Warnings: SEVERE NEUTROPENIA (associated with an increased risk of serious and potentially fatal infections; requires baseline ANC monitoring and is not recommended if baseline ANC is less than 1500/mm³); ORTHOSTATIC HYPOTENSION, BRADYCARDIA, AND SYNCOPE; SEIZURE; MYOCARDITIS, PERICARDITIS, AND CARDIOMYOPATHY; INCREASED MORTALITY IN ELDERLY PATIENTS WITH DEMENTIA-RELATED PSYCHOSIS.
- Patients must be monitored for severe neutropenia (requiring Absolute Neutrophil Count (ANC) monitoring), orthostatic hypotension, bradycardia, syncope, falls, seizures, myocarditis, pericarditis, cardiomyopathy, mitral valve incompetence, increased mortality in elderly patients with dementia-related psychosis, gastrointestinal hypomotility with severe complications, eosinophilia, QT interval prolongation, neuroleptic malignant syndrome, and metabolic changes including hyperglycemia, diabetes mellitus, dyslipidemia, and weight gain.
- Use with extreme caution in patients with kidney impairment, diabetes (raised blood sugar level), cardiovascular disease (disease of the vessels of the heart), liver impairment, respiratory disorders, pheochromocytoma (benign tumor of adrenal gland), epilepsy (abnormal brain activity), urinary retention, or prostatic hypertrophy (enlargement of prostate gland).
- Patients should be advised not to discontinue this medicine unless instructed by a healthcare professional.
How it Works (Mechanism of Action)
The mechanism of action of clozapine is unknown. However, it has been proposed that the therapeutic efficacy in schizophrenia is mediated through antagonism of the dopamine type 2 (D2) and the serotonin type 2A (5-HT2A) receptors. Clozapine also acts as an antagonist at adrenergic, cholinergic, histaminergic, and other dopaminergic and serotonergic receptors.
Commercial Brands (Alternatives)
No other brands found for this formula.