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Olanzapine

Generic Name: olanzapine (oral) (oh LANZ a peen)
Brand Name: ZyPREXA, ZyPREXA Zydis

Medically reviewed by Drugs.com on Apr 28, 2020 – Written by Cerner Multum

What is olanzapine?

Olanzapine is an antipsychotic medication that is used to treat psychotic conditions such as schizophrenia and bipolar disorder (manic depression) in adults and children at least 13 years old.

Olanzapine is also used together with fluoxetine (Prozac) to treat episodes of depression in adults and children at least 10 years old who have bipolar I disorder.

Olanzapine may also be used for purposes not listed in this medication guide.

Important Information

Olanzapine is not approved for use in older adults with dementia-related psychosis.

Before taking this medicine

You should not take olanzapine if you are allergic to it.

Olanzapine may increase the risk of death in older adults with dementia-related psychosis and is not approved for this use.

Tell your doctor if you have ever had:

Taking antipsychotic medicine in the last 3 months of pregnancy may cause breathing problems, feeding problems, or withdrawal symptoms in the newborn. If you get pregnant, tell your doctor right away. Do not stop taking olanzapine without your doctor's advice.

Olanzapine can pass into breast milk. If you are breastfeeding, tell your doctor if you notice severe drowsiness, irritability, feeding problems, tremors, or unusual muscle movements in the nursing baby.

The olanzapine orally disintegrating tablet (Zyprexa Zydis) may contain phenylalanine. Tell your doctor if you have phenylketonuria (PKU).

How should I take olanzapine?

Follow all directions on your prescription label and read all medication guides or instruction sheets. Your doctor may occasionally change your dose. Use the medicine exactly as directed.

Olanzapine can be taken with or without food.

Remove an orally disintegrating tablet (Zyprexa Zydis) from the package only when you are ready to take the medicine. Place the tablet in your mouth and allow it to dissolve, without chewing. Swallow several times as the tablet dissolves.

Olanzapine can cause high blood sugar (hyperglycemia). If you are diabetic, check your blood sugar levels on a regular basis.

You may gain weight or have high cholesterol and triglycerides (types of fat) while taking olanzapine, especially if you are a teenager. You may need frequent blood tests.

Call your doctor if your symptoms do not improve, or if they get worse while using olanzapine.

Do not stop using olanzapine suddenly, even if you feel fine. Stopping suddenly may cause serious side effects.

Olanzapine is sometimes used together with other antipsychotic medications or antidepressants. Use all medications as directed and read all medication guides you receive. Do not change your dose or dosing schedule without your doctor's advice.

Medication may be only part of a complete program of treatment that also includes counseling and other psychological support programs. Follow your doctor's instructions.

Store at room temperature away from moisture, heat, and light.

What happens if I miss a dose?

Take the medicine as soon as you can, but skip the missed dose if it is almost time for your next dose. Do not take two doses at one time.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

Overdose symptoms may include drowsiness, agitation, aggression, slurred speech, confusion, increased heart rate, jerky or uncontrolled muscle movements, trouble breathing, or fainting.

What should I avoid while taking olanzapine?

Avoid driving or hazardous activity until you know how olanzapine will affect you. Dizziness or drowsiness can cause falls, accidents, or severe injuries.

Avoid getting up too fast from a sitting or lying position, or you may feel dizzy.

Avoid drinking alcohol. Dangerous side effects could occur.

Avoid becoming overheated or dehydrated. Drink plenty of fluids, especially in hot weather and during exercise. It is easier to become dangerously overheated and dehydrated while you are taking olanzapine.

Olanzapine side effects

Get emergency medical help if you have signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Seek medical treatment if you have a serious drug reaction that can affect many parts of your body. Symptoms may include: skin rash, fever, swollen glands, muscle aches, severe weakness, unusual bruising, or yellowing of your skin or eyes.

High doses or long-term use of olanzapine can cause a serious movement disorder that may not be reversible. The longer you use olanzapine, the more likely you are to develop this disorder, especially if you are a woman or an older adult.

Call your doctor at once if you have:

  • uncontrolled muscle movements in your face (chewing, lip smacking, frowning, tongue movement, blinking or eye movement);

  • trouble speaking or swallowing;

  • swelling in your hands or feet;

  • confusion, unusual thoughts or behavior, hallucinations, or thoughts about hurting yourself;

  • low white blood cell counts--fever, chills, mouth sores, skin sores, sore throat, cough, trouble breathing, feeling light-headed; or

  • signs of dehydration--feeling very thirsty or hot, being unable to urinate, heavy sweating, or hot and dry skin;

  • liver problems--upper stomach pain, itching, loss of appetite, dark urine, clay-colored stools, jaundice (yellowing of the skin or eyes);

  • high blood sugar--increased thirst, increased urination, hunger, dry mouth, fruity breath odor, drowsiness, dry skin, blurred vision, weight loss; or

  • severe nervous system reaction--very stiff (rigid) muscles, high fever, sweating, confusion, fast or uneven heartbeats, tremors, feeling like you might pass out.

Common side effects may include:

  • weight gain (more likely in teenagers), increased appetite;

  • headache, dizziness, drowsiness, feeling tired or restless;

  • problems with speech or memory;

  • tremors or shaking, numbness or tingly feeling;

  • changes in personality;

  • dry mouth, or increased salivation;

  • stomach pain, constipation; or

  • pain in your arms or legs.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

What other drugs will affect olanzapine?

Taking olanzapine with other drugs that make you sleepy or slow your breathing can cause dangerous or life-threatening side effects. Ask your doctor before using opioid medication, a sleeping pill, a muscle relaxer, or medicine for anxiety or seizures.

Other drugs may affect olanzapine, including prescription and over-the-counter medicines, vitamins, and herbal products. Tell your doctor about all your current medicines and any medicine you start or stop using.

Further information

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.