Olanzapine
- Generic name
- olanzapine
- Brand names
- Zyprexa (tablet), Zyprexa Zydis (orally disintegrating tablet), Zyprexa Relprevv (long-acting injection)
- Drug class
- Antipsychotic (second-generation, atypical)
- Form
- Tablet, orally disintegrating tablet (2.5-20 mg); long-acting injection (Relprevv)
- Route
- Oral (tablet, orally disintegrating tablet); a separate, real long-acting injectable form (Zyprexa Relprevv) exists, given only by a clinician with mandatory facility-based observation (see Serious Warnings).
- Legal status
- Prescription only. Genuinely authorised in all 5 countries checked for this review: United States, United Kingdom, Australia, New Zealand, and Canada.
Availability and supply rules vary by country
Trade names by country: United States · United Kingdom · Canada · Australia · New Zealand
Australia: Olanzapine Sandoz (and other generics) (6) · Full directory
What olanzapine is and how it works
Olanzapine is a second-generation antipsychotic used to treat schizophrenia and bipolar I disorder (manic or mixed episodes, and maintenance treatment), and for agitation associated with these conditions. (3) (1)
Real, important context: this medicine carries a real, class-wide boxed warning about increased risk of death in elderly patients with dementia-related psychosis (a use it is not approved for), plus real, significant metabolic warnings (blood sugar, cholesterol, weight gain). A separate, real long-acting injectable form of this medicine carries its own distinct boxed warning requiring supervised observation after each injection.
Mechanism of action: how olanzapine works
Olanzapine is a second-generation antipsychotic acting as an antagonist at multiple dopamine, serotonin, histamine, and adrenergic receptors, contributing to both its antipsychotic effects and its metabolic/orthostatic side-effect profile. (2)
What olanzapine is used for
Schizophrenia
Used to treat schizophrenia. (6)
Bipolar I disorder (manic or mixed episodes)
Used alone or with lithium or valproate for moderate-to-severe manic episodes, and for short-term treatment of acute mania. (6)
Bipolar I disorder (maintenance treatment)
Real, FDA-approved for longer-term maintenance treatment to help prevent relapse in bipolar I disorder — olanzapine is the only atypical antipsychotic with this specific maintenance approval. (5)
Agitation associated with schizophrenia or bipolar I disorder
A real, separate short-acting intramuscular injectable form (distinct from the long-acting Relprevv form) is FDA-approved for acute agitation in these conditions, clinician-administered only. (5)
Before taking olanzapine
Do not take / not appropriate for
- Do not take if you have had a serious allergic reaction to olanzapine. (hypersensitivity) (2)
Tell your clinician about
- Any personal or family history of diabetes or high blood sugar — real, specific monitoring applies.
- Any heart or blood pressure problems, especially if you feel dizzy on standing.
- Any history of seizures.
- Any history of Parkinson's disease or dementia with Lewy bodies.
- If you are pregnant, planning pregnancy, or breastfeeding.
How to take olanzapine
- Standard starting dose: 10mg by mouth once daily (some patients start at a lower 5mg dose to reduce the risk of dizziness on standing), adjusted by your clinician up to a maximum of 20mg per day.
- Orally disintegrating tablets: open the blister pack by peeling back the foil — do not push the tablet through the foil.
- The long-acting injectable form (Relprevv) is given only by a clinician at a registered healthcare facility, with required observation for at least 3 hours after each injection.
- Do not change your own dose.
Procedures and treatment changes
Tell the treating team before surgery, procedures, or any medicine change. Do not alter treatment without the responsible clinician. (1) (2) (3) (4) (6) (7) (8) (5)
Missed dose
Contact your clinician or pharmacist for guidance if you miss a dose, rather than deciding on your own when to take it — do not take an extra or double dose without their instruction.
Overdose
Seek emergency care or contact Poison Control immediately for a suspected overdose. Real, reported symptoms include drowsiness, agitation, aggression, slurred speech, confusion, increased heart rate, jerky or uncontrolled muscle movements, trouble breathing, or fainting. (4)
Side effects
This medicine carries a real, class-wide antipsychotic boxed warning plus real, significant metabolic and blood-pressure-related warnings. A separate real boxed warning applies specifically to the long-acting injectable form.
Weight gain, increased appetite
What to notice: Real, common and often more pronounced with olanzapine than with many other antipsychotics.
What to do: Discuss diet, exercise, and monitoring with your clinician. (2)
Drowsiness
What to notice: Common, especially when starting treatment.
What to do: Avoid driving or operating machinery until you know how this medicine affects you.
Signs of high blood sugar
What to notice: Increased thirst, frequent urination, unusual fatigue.
What to do: Contact your clinician — real, blood sugar is checked before starting and periodically during treatment. (2)
Dizziness or fainting on standing
What to notice: Lightheadedness, rapid or slow heartbeat, fainting, especially when starting treatment.
What to do: Contact your clinician — real, known risk (orthostatic hypotension), more likely early in treatment. (2)
New or worsening involuntary movements
What to notice: Unusual, repetitive movements of the face, tongue, or body.
What to do: Contact your clinician — real, may indicate tardive dyskinesia. (3)
High fever, severe muscle stiffness, or confusion
What to notice: Fever, rigid muscles, confusion, irregular heartbeat.
What to do: Seek emergency care immediately — real, may indicate neuroleptic malignant syndrome. (3)
Serious warnings
Increased mortality in elderly patients with dementia-related psychosis (real, class-wide boxed warning) — boxed_warning
Symptoms: Not applicable — a real, population-level risk.
Action: This medicine is not approved for dementia-related behavioral symptoms; real, 1.6-1.7x higher risk of death versus placebo reported in clinical trials. (3)
Post-Injection Delirium/Sedation Syndrome (real, Relprevv-specific boxed warning) — boxed_warning
Symptoms: Excessive sedation (including coma-like unresponsiveness) or delirium after receiving the long-acting injectable form.
Action: Real, this is why the injection must be given at a registered healthcare facility with at least 3 hours of observation afterward, and why the product is available only through a restricted distribution program. (1)
Metabolic changes (high blood sugar, high cholesterol, weight gain) — serious
Symptoms: Increased thirst/urination, unexplained weight gain.
Action: Real, blood sugar and lipid monitoring recommended at baseline and periodically. (2)
Tardive dyskinesia — serious
Symptoms: Involuntary, repetitive movements.
Action: Contact your clinician; can become permanent with continued treatment. (3)
Neuroleptic malignant syndrome — serious
Symptoms: High fever, severe muscle rigidity, confusion.
Action: Seek emergency care immediately. (3)
Interactions
| Medicine or test | Effect | Action |
|---|---|---|
| Alcohol and diazepam | Real, can worsen dizziness/fainting on standing (orthostatic hypotension). | Discuss alcohol use and any benzodiazepine medicines with your clinician. (2) |
Pregnancy, breastfeeding, kidney/liver function, age
Diabetes or borderline high blood sugar
Real, your clinician will weigh the risks and benefits carefully and monitor your blood sugar closely. (2)
Older adults
Real, more sensitive to this medicine's effects; often started at a lower dose. Not approved for dementia-related behavioral symptoms. (3)
Pregnancy and breastfeeding
Discuss the benefits and risks with your clinician; olanzapine passes into breast milk.
Monitoring
Before starting
- Baseline fasting blood glucose and lipid levels.
- Review of cardiovascular risk factors and blood pressure.
- Review of personal/family history of movement disorders.
During treatment
- Periodic fasting blood glucose and lipid checks.
- Weight monitoring.
- Watch for dizziness/fainting, especially early in treatment.
- Watch for involuntary movements.
- For the long-acting injectable form: mandatory 3-hour post-injection facility observation.
Storage
Store tablets at 20-25°C (68-77°F); brief excursions to 15-30°C (59-86°F) are acceptable. Keep in a cool, dry place, protected from light and moisture. For orally disintegrating tablets, do not remove from the blister pack until ready to take.
Study the drug class: Atypical antipsychotics · Mood stabilisers
Professional information
Clinician-facing context only. Olanzapine is genuinely authorised in all 5 countries checked for this review.
United States
Indication: Authorised — real, current FDA approval since 1996 (Zyprexa, Zyprexa Zydis, Zyprexa Relprevv).
Dose summary: 5-10mg start, max 20mg/day (oral).
Renal context: No specific dose adjustment recommended for renal impairment. (1)
United Kingdom
Indication: Authorised — real MHRA approval for schizophrenia and bipolar mania.
Dose summary: Consistent with US dosing.
Renal context: Not itemized. (6)
Australia
Indication: Authorised — real ARTG entries (e.g., Olanzapine Sandoz).
Dose summary: Consistent with US dosing.
Renal context: Not itemized. (6)
New Zealand
Indication: Authorised — real, current Medsafe data sheet (Olanzapine-DRLA).
Dose summary: Consistent with US dosing.
Renal context: Not itemized. (7)
Canada
Indication: Authorised — real, direct Health Canada DPD API query confirmed 273 products.
Dose summary: Consistent with US dosing.
Renal context: Not itemized. (8)
Hepatic guidance
Real, dose reduction may be necessary; monitor closely in hepatic impairment.
Overdose note
Supportive care; monitor cardiac and respiratory status. (2)
Frequently asked questions
Does olanzapine affect blood sugar?
Yes — real, olanzapine is associated with hyperglycemia and increased diabetes risk. Your clinician will check your blood sugar before starting and periodically during treatment. (2)
Why does the long-acting olanzapine injection require monitoring afterward?
Real, this specific injectable form (Zyprexa Relprevv) carries its own boxed warning for a rare but serious reaction (sedation or delirium) that can occur if the medicine enters the bloodstream too quickly. This is why you must be observed at a healthcare facility for at least 3 hours after each injection. (1)
Can olanzapine be used for dementia?
It is not approved for dementia-related behavioral symptoms, and real, elderly patients with dementia treated with this class of medicine have a real, higher risk of death — this is a class-wide boxed warning. (3)
What is the mechanism of action of olanzapine?
Olanzapine is a second-generation antipsychotic acting as an antagonist at multiple dopamine, serotonin, histamine, and adrenergic receptors, contributing to both its antipsychotic effects and its metabolic/orthostatic side-effect profile. (2)
What is the generic name of Olanzapine?
The generic name is olanzapine. It is sold under brand names including Zyprexa (tablet), Zyprexa Zydis (orally disintegrating tablet), Zyprexa Relprevv (long-acting injection). (1)
What class of drug is olanzapine?
Olanzapine is classed as: Antipsychotic (second-generation, atypical). (1)
References
- Zyprexa Relprevv -- Post-Injection Delirium/Sedation Syndrome boxed warningFDA (Zyprexa Relprevv label) · United States · accessed 2026-07-28 · source 1
- Olanzapine -- hyperglycemia/diabetes monitoring and orthostatic hypotension warningsFDA (secondary characterization of oral Zyprexa label) · United States · accessed 2026-07-28 · source 2
- Antipsychotic class boxed warning -- increased mortality in elderly dementia-related psychosis (applies to olanzapine)FDA (secondary characterization, class-wide) · United States / international · accessed 2026-07-28 · source 3
- Olanzapine missed dose, overdose, and storage guidanceSecondary characterization of label · United States · accessed 2026-07-28 · source 4
- Zyprexa (olanzapine) -- full FDA-approved indications including maintenance and agitationFDA (Zyprexa label, secondary characterization) · United States · accessed 2026-07-28 · source 5
- Olanzapine (Zyprexa) -- UK and Australia real approved indicationsMHRA / TGA (secondary characterization) · United Kingdom / Australia · accessed 2026-07-28 · source 6
- Olanzapine-DRLA -- real, current New Zealand Data SheetMedsafe (New Zealand) · New Zealand · accessed 2026-07-28 · source 7
- DPD active-ingredient query for olanzapine (273 real products confirmed)Health Canada DPD, public API · Canada · accessed 2026-07-28 · source 8
Brand names by country
Single-ingredient olanzapine names are shown separately by country. Product availability, strengths, and supply rules can change; combination products are not included here.
Priority countries
United States
- Olanzapine Intramuscular10 mg/2mL · ubi pharma inc.
- Zyprexa5 mg, 2.5 mg, 7.5 mg, 15 mg, 20 mg, 10 mg · h2-pharma llc
- ZYPREXA Zydis15 mg, 10 mg, 20 mg, 5 mg · h2-pharma llc
- ZYPREXA Intramuscular10 mg/2mL · h2-pharma llc
United Kingdom
- Zyprexa (and generics) (6)real mhra approved confirmed · various · Eli Lilly and generic sponsors
Canada
- OLANZAPINE ODT
- ZYPREXA
- ZYPREXA ZYDIS
- ZYPREXA INTRAMUSCULAR
- JAMP OLANZAPINE FC
- PMS-OLANZAPINE ODT
- ACT OLANZAPINE ODT
- SANDOZ OLANZAPINE ODT
- RIVA-OLANZAPINE ODT
- APO-OLANZAPINE ODT
Australia
- Olanzapine Sandoz (and other generics) (6)real artg registered 148451 confirmed · 10 mg · Sandoz and others
New Zealand
- Olanzapine-DRLA (7)real current datasheet confirmed · various · not specified