Indications for Clozapine Orally-Disintegrating Tabs:
Treatment-resistant schizophrenia. To reduce risk of recurrent suicidal behavior in schizophrenia or schizoaffective disorders.
Dissolve tablet in mouth. Initially 12.5mg 1–2 times daily; may increase by 25–50mg/day to 300–450mg/day in divided doses by the end of 2 weeks. Then may increase once or twice weekly in increments of up to 100mg; max 900mg/day. Reevaluate periodically. Reduce gradually over 1–2 weeks if discontinuing; can discontinue abruptly if necessary (eg, severe neutropenia, myocarditis; may cause relapse or cholinergic rebound). Retitrate if stopped for ≥2 days. Caution with rechallenge (see full labeling). Dose adjustments with concomitant inhibitors or inducers: see full labeling. Renal or hepatic impairment, CYP2D6 poor metabolizers: may need to reduce dose.
Severe neutropenia. Orthostatic hypotension, syncope, and bradycardia. Seizure. Myocarditis and cardiomyopathy. Increased mortality in elderly patients with dementia-related psychosis.
See full labeling. Risk of severe neutropenia; obtain CBC and confirm baseline ANC ≥1500/μL (≥1000/μL if benign ethnic neutropenia) prior to initiation. Monitor WBC and ANC weekly for 1st 6 months and for 4 weeks after discontinuing; if acceptable WBC and ANC maintained, may reduce monitoring to every 2 weeks after 6 months, then every 4 weeks after 12 months. Increased mortality in elderly with dementia-related psychosis (not approved use). Cardio- or cerebrovascular disease. Conditions that would predispose to hypotension (eg, concomitant antihypertensives, dehydration, hypovolemia). Perform fall risk assessments when initiating and recurrently on long-term therapy. History of or risk factors for seizure. Monitor for myocarditis or cardiomyopathy; discontinue if suspected. Increased risk of QT prolongation; discontinue if interval >500msec. Significant cardiac arrhythmia. Recent MI. Uncompensated heart failure. Consider obtaining baseline ECG and serum chemistry panel. Correct electrolyte abnormalities prior to starting; obtain baseline serum potassium and magnesium levels; monitor periodically thereafter. Monitor for hyperglycemia. Diabetes or risk factors thereof. Monitor for hepatotoxicity; consider permanently discontinuing if clozapine-associated hepatitis or elevated transaminases occur. Exclude severe neutropenia, infection, neuroleptic malignant syndrome if fever occurs. Narrow-angle glaucoma. Constipation (screen and treat prior to initiation). Urinary retention. Significant prostatic hypertrophy. Renal or hepatic impairment. CYP2D6 poor metabolizers. Use lowest effective dose for shortest duration. Neonates: risk of extrapyramidal and/or withdrawal symptoms post delivery (due to exposure during 3rd-trimester pregnancy). Pregnancy (Cat.B). Nursing mothers: not recommended.
Caution with drugs that affect or are affected by CYPA1A2, 2D6, 3A4. Concomitant strong CYP1A2 inhibitors (eg, fluvoxamine, ciprofloxacin, or enoxacin): reduce clozapine dose by ⅓. Concomitant moderate or weak CYP1A2 inhibitors (eg, oral contraceptives, caffeine), CYP2D6 or 3A4 inhibitors (eg, cimetidine, escitalopram, erythromycin, paroxetine, bupropion, fluoxetine, quinidine, duloxetine, terbinafine, sertraline): monitor and reduce clozapine dose if needed. Concomitant strong CYP3A4 inducers (eg, phenytoin, carbamazepine, St. Johns wort, rifampin): not recommended; may need to increase clozapine dose. Concomitant weak or moderate CYP1A2 (eg, tobacco smoking) or 3A4 inducers: monitor and increase clozapine dose if needed. Caution with concomitant drugs known to prolong the QT interval: certain antipsychotics (eg, ziprasidone, iloperidone, chlorpromazine, thioridazine, mesoridazine, droperidol, pimozide), antibiotics (eg, erythromycin, gatifloxacin, moxifloxacin, sparfloxacin), Class IA or Class III antiarrhythmics (eg, quinidine, procainamide, amiodarone, sotalol), and others (eg, pentamidine, levomethadyl acetate, methadone, halofantrine, mefloquine, dolasetron mesylate, probucol, tacrolimus). Caution with drugs that can cause electrolyte imbalance (eg, diuretics). Increased risk for anticholinergic toxicity, severe GI hypomotility effects when concomitant other anticholinergic drugs (eg, benztropine, cyclobenzaprine, diphenhydramine); avoid use when possible. May potentiate antihypertensives, CNS drugs. May potentiate other drugs that are metabolized by CYP2D6 (eg, certain antidepressants, phenothiazines, carbamazepine, propafenone, flecainide, encainide); may need to use lower doses of these. Neuroleptic malignant syndrome possible with concomitant lithium.
Sedation, dizziness/vertigo, headache, tremor, tachycardia, hypotension, syncope, hypersalivation, sweating, dry mouth, visual disturbances, constipation, nausea, fever; severe neutropenia, seizures, bradycardia, weight gain, hyperglycemia, dyslipidemia, myocarditis, cardiomyopathy, eosinophilia, neuroleptic malignant syndrome, anticholinergic toxicity, thrombosis, pulmonary embolism, tardive dyskinesia, hepatotoxicity, GI hypomotility with severe complications.
Formerly known under the brand name Fazaclo.