| Efficacy |
| Schizophrenia (FDA approved for all) |
| Treatment-resistant schizophrenia (clozapine) |
| Mania (FDA approved for olanzapine) |
| Depression/anxiety/agitation (efficacy established but not FDA approved for these purposes) |
| Side effects |
| Weight gain |
| Sedation |
| Akathisia |
| Orthostatic hypotension |
| Dizziness |
| ↑ Triglycerides |
| EPS, NMS (rare) |
| Agranulocytosis (clozapine) (rare) |
| Seizures (clozapine) |
| Safety in overdose |
| Seizures with clozapine in overdose. Respiratory depression in combination with other CNS depressants. QT interval changes. Lavage and vital sign support |
| Dosage and administration |
| Clozapine: 12.5—25 mg; then increase dosage 25—50 mg per week, as needed and tolerated, to 300—600 mg/day |
| Risperidone: 0.5—1 mg b.i.d. to 3 mg b.i.d. by end of first week, as tolerated |
| Olanzapine: 2.5—5 mg h.s.; increase by 5 mg every week to 20 mg h.s. |
| Quetiapine: 25 mg b.i.d.; increase total daily dose by 50 mg, as needed and tolerated, to 300—600 mg/day |
| Ziprasidone: 20 mg/day or b.i.d.; increase by 20—40 mg per week, to a maximum dosage of 80 mg b.i.d. |
| Aripiprazole: 15 mg/day; increase up to 30 mg/day after 1 week |
| Full benefits in 4 weeks to 6 months |
| Discontinuation |
| Mild cholinergic rebound, faster relapse |
| Taper as slowly as titrated up |
| Drug interactions |
| Fluvoxamine (1A2 inhibitors): ↑ atypical antipsychotic levels |
| EtOH: ↑ sedation and orthostasis |
| Antihypertensives: may ↑ orthostasis |
| Carbamazepine: ↓ serum levels of olanzapine; contraindicated with clozapine |
| CNS depressants: ↑ sedation |
| CNS = central nervous system; EPS = extrapyramidal symptoms; EtOH = ethanol; FDA = U.S. Food and Drug Administration; NMS = neuroleptic malignant syndrome |
Reprinted with permission from Schatzberg AF, Cole J, DeBattista C: Antipsychotic drugs, in Manual of Clinical Psychopharmacology, 4th ed. Arlington, Va, American Psychiatric Publishing, Inc, 2003, pp 188—189. |