Antipsychotic agents
Agent | Haloperidol | Olanzapine | Quetiapine | Risperidone | Aripiprazole |
---|---|---|---|---|---|
Dosage forms | Oral tablets, solution Intramuscular and intravenous solutions | Oral tablets, disintegrating tablets Intramuscular solution | Oral tablets, solution | Oral tablets, disintegrating tablets, solution | Oral tablets, solution, distintegrating tablets Intramuscular solution |
Starting dose | 0.5–1 mg twice a day | 2.5–5 mg twice a day | 12.5–25 mg twice a day | 0.5 mg twice a day | 1 mg twice a day |
Half-life (hours) | 12–38 | 21–54 | 6 | 20 | 75 |
Clearance | Hepatic | Hepatic | Hepatic | Hepatic | Hepatic |
Common adverse effects | Akathisia Dystonia Parkinsonism | Akathisia Parkinsonism | Agitation | Parkinsonism | Akathisia Agitation |
Effects on corrected QT interval | Oral, intramuscular: Mild Intravenous: Moderate | Mild | Mild | Mild | None |
Orthostatic hypotension | Mild | Moderate | Severe | Severe | Moderate |
Anticholinergic effectsa | Mild | Severe | Moderate | Mild | Mild |
Sedation | Mild | Moderate | Severe | Moderate | Moderate |
Drug-drug interactions (CYP450 activity) | Substrate of: CYP1A2 (minor) CYP2D6 (major) CYP3A4 (major) Inhibits CYP2D6 (moderate) | Substrate of: CYP1A2 (major) CYP2D6 (minor) | Substrate of: CYP2D6 (minor) CYP3A4 (major) | Substrate of: CYP2D6 (major) CYP3A4 (minor) | Substrate of: CYP2D6 (major) CYP3A4 (major) |
Special considerations | Minimal effect on vital signs May worsen stiffness and motor symptoms in Parkinson disease | Comes in dissolvable form Helpful for cancer-related nausea Do not combine with parenteral benzodiazepines due to risk of respiratory depression May worsen control of diabetes | Consider in Parkinson disease | Comes in dissolvable form | May be useful for hypoactive delirium No known effect on QTc |
↵a Dry mouth, constipation, urinary retention.
Based on information from references 23–25.