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Olanzapine

Brand names: Zyprexa, Zyprexa Zydis, Lybalvi (with samidorphan)

Olanzapine is an antipsychotic for schizophrenia and bipolar disorder. It often causes weight gain.

Brand namesZyprexa, Zyprexa Zydis, Lybalvi (with samidorphan)
Type of medicineAntipsychotic
Prescription?Prescription
ImportantThis page is general information, not a prescription. Don't start, stop, or change a medicine without talking to your provider or pharmacist.

Overview

It's also combined with fluoxetine (Symbyax) for bipolar or treatment-resistant depression.

What it's used for

  • Schizophrenia
  • Bipolar mania and maintenance
  • Off-label: nausea from chemotherapy

How to take it

  • Take it once a day, with or without food, often in the evening.
  • Dissolving tablets melt on the tongue.
  • Don't stop suddenly.

Your dose depends on your health and other medicines. Always follow your prescription label, and ask your pharmacist if anything is unclear.

Side effects

Common side effects

  • Weight gain and more appetite
  • Sleepiness
  • Dry mouth
  • Constipation
  • Dizziness
Call 911Thoughts of suicide or harming yourself. Call or text 988 any time.
Call 911High fever, stiff muscles, confusion, and sweating (rare reaction called NMS)
Call your provider todayUncontrolled movements of the face, tongue, or body
Call your provider todayExtreme thirst, peeing a lot, or very high blood sugar
Call 911Rash with fever, swollen glands, and face swelling (rare DRESS reaction)

Warnings

  • Boxed warnings: higher risk of death in older adults with dementia, and suicidal thoughts in young people.
  • It can raise blood sugar, cholesterol, and weight; your provider will check these.
  • It can make you overheat; avoid getting too hot and stay hydrated.

Other medicines, foods, and alcohol

  • Smoking lowers its level; quitting can raise it.
  • Fluvoxamine and ciprofloxacin raise its level.
  • Alcohol and sedating medicines add to drowsiness. Don't combine with benzodiazepine shots.

Tell your provider and pharmacist about every medicine, vitamin, and supplement you take.

Pregnancy and breastfeeding

Talk with your provider about benefits and risks. Don't stop on your own.

Missed doses, overdose, and storage

If you miss a dose

Take it as soon as you remember, unless it's almost time for your next dose. Then skip the missed dose. Don't take two doses at once.

If someone takes too much

Call Poison Control at 1-800-222-1222 or get help online at poison.org. Call 911 if the person collapses, has a seizure, has trouble breathing, or can't be woken.

Storing it

Store at room temperature, away from heat and moisture (not in the bathroom), and out of reach of children and pets.

Conditions it's used for

Sources

Last updated 2026-11-13.