Acute treatment of schizophrenia.
≥18yrs: 1mg twice daily on day 1, 2mg twice daily on day 2, 4mg twice daily on day 3, 6mg twice daily on day 4, 8mg twice daily on day 5, 10mg twice daily on day 6, 12mg twice daily on day 7; target range 6–12mg twice daily; max 24mg/day. Reduce dose by ½ with concomitant strong CYP2D6/CYP3A4 inhibitors, or poor metabolizers of CYP2D6. Retitrate if therapy suspended >3 days. Reassess periodically.
<18yrs: not recommended.
Increased mortality in elderly patients with dementia-related psychosis (not approved use). Bradycardia, hypokalemia, hypomagnesemia, congenital QT prolongation, recent MI, uncompensated heart failure, arrhythmias: avoid (risk of torsades de pointes/ sudden death). Cardio- or cerebrovascular disease. Monitor electrolytes esp. K+, Mg++. Hepatic impairment: not recommended. Diabetes or risk factors (obtain baseline fasting blood sugar). Monitor for hyperglycemia, weight changes. History of breast cancer or seizures. Orthostatic hypotension. Preexisting low WBC count or history of leukopenia/neutropenia: monitor CBC during 1st few months of therapy; discontinue if WBCs decline. Exposure to extreme heat. Dehydration. Suicidal tendencies. Write ℞ for the smallest practical amount. Monitor for neuroleptic malignant syndrome. Neonates: risk of extrapyramidal and/or withdrawal symptoms post delivery (due to exposure during 3rd-trimester pregnancy). Pregnancy (Cat.C). Nursing mothers: not recommended.
Avoid other drugs that cause QT prolongation (eg, quinidine, amiodarone, sotalol, procainamide, chlorpromazine, thioridazine, moxifloxacin, methadone). May potentiate antihypertensives. Caution with alcohol, CNS depressants. Potentiated by inhibitors of CYP2D6 (eg, fluoxetine, paroxetine) or CYP3A4 (eg, clarithromycin, ketoconazole).
Dizziness, dry mouth, fatigue, nasal congestion, orthostatic hypotension, somnolence, tachycardia, increased weight; QT prolongation (discontinue if QTc >500msec persists), priapism, neuroleptic malignant syndrome, tardive dyskinesia, hyperglycemia, dyslipidemia, dysphagia, hyperprolactinemia.
Tabs—60; Titration pack—8 (2 x 1mg, 2 x 2mg, 2 x 4mg, 2 x 6mg)