Section 19 · Monograph
Olanzapine
Reviewed Nov 2026FDA label
ZyprexaAtypical antipsychotic
- Forms
- Tab: 2.5, 5, 7.5, 10, 15, 20mg | ODT | IM: 10mg
- Dose
- Delirium or refractory nausea (off-label): 2.5-5mg at bedtime or divided; titrate cautiously
- MOA
- D2, 5-HT2A, H1 and muscarinic antagonism
Black Box Warning
- Increased mortality in elderly patients with dementia-related psychosis; not approved for dementia-related psychosis
Indications
- Schizophrenia and bipolar I disorderFDA-labeled
- Agitation associated with schizophrenia or bipolar mania (IM)FDA-labeled
- Chemotherapy-induced nausea and vomiting (with other agents) in some guidelinesFDA-labeled
Off-Label Uses
- Delirium and refractory nausea in palliative and neurologic careOff-label
Mechanism of Action
- Atypical antipsychotic with D2, 5-HT2A, histamine H1, muscarinic and alpha-1 receptor antagonism
Full Dosing
Adult / usual
- Delirium or nausea (off-label): 2.5-5mg at bedtime or divided twice daily; titrate cautiously
- Start 2.5mg in older or frail patients; ODT forms are useful when swallowing is difficult
- Monitor sedation and orthostasis
Contraindications
- Hypersensitivity to olanzapine
- IM olanzapine: concurrent parenteral benzodiazepine use is not recommended (cardiorespiratory depression)
Drug Interactions
- Additive sedation with benzodiazepines, opioids and alcohol
- Avoid in Parkinson's disease and dementia with Lewy bodies where possible (worsens motor symptoms)
- CYP1A2 inhibitors (fluvoxamine, ciprofloxacin) raise levels; smoking lowers levels
Adverse Effects
- Sedation, weight gain and metabolic effects
- Orthostatic hypotension
- Anticholinergic effects
- Extrapyramidal symptoms (less than haloperidol)
- Hyperglycemia
Monitoring Parameters
- Sedation, orthostatic blood pressure and extrapyramidal symptoms
- Weight, glucose and lipids with long-term use
- Delirium or nausea response
Pregnancy & Lactation
- Limited data; third-trimester exposure may cause neonatal extrapyramidal or withdrawal symptoms
- Present in milk; monitor infants