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Olanzapine, Oral/Injection

What are other names for this medicine?

Type of medicine: antipsychotic

Generic and brand names: olanzapine, oral; Zyprexa; Zyprexa Zydis; Zyprexa IntraMuscular

What is this medicine used for?

This medicine is taken by mouth or given by injection to treat the symptoms of mental disorders such as schizophrenia and bipolar mania.

It may be used for other conditions as determined by your healthcare provider.

What should my healthcare provider know before I take this medicine?

Before taking this medicine, tell your healthcare provider if you have ever had:

  • an allergic reaction to any medicine
  • Alzheimer's disease or dementia
  • breast cancer
  • diabetes
  • an enlarged prostate or trouble urinating
  • glaucoma
  • heart disease, a heart attack, stroke, or heart failure
  • low blood pressure
  • liver disease
  • myasthenia gravis
  • phenylketonuria (PKU) (The disintegrating tablet contains phenylalanine.)
  • seizures
  • trouble swallowing.

Tell your healthcare provider if you are taking or planning to take any other prescription or nonprescription medicines during treatment with this medicine.

Females of childbearing age: Tell your healthcare provider if you are pregnant or plan to become pregnant while taking this medicine. It is not known whether this medicine will harm an unborn baby. Do not breast-feed while taking this medicine.

How do I use it?

Shots of this medicine will be given by a healthcare provider.

If you have the tablets, take them with a glass of water, with or without food. Usually your healthcare provider will start you with a small dosage and increase it gradually after several days. Take this medicine exactly as directed by your healthcare provider. Do not increase the dosage on your own.

If you have the disintegrating tablets, make sure your hands are dry before you handle the tablet. Do not open the blister pack that contains the tablet until you are ready to take it. Peel back the foil, then take the tablet out. Do not push the tablet through the foil. Place the tablet in your mouth and let it melt quickly.

Do not stop taking this medicine without your healthcare provider's approval. Your dosage may need to be reduced gradually.

If you miss a dose, do not take a double dose the next day. If you are not sure of what to do if you miss a dose, or if you miss more than one dose, contact your healthcare provider.

What should I watch out for?

This medicine can cause low blood pressure, especially at the beginning of treatment or when taken with alcohol or diazepam (Valium). Low blood pressure may make you feel lightheaded or dizzy. Take care to avoid falling.

Older adults with dementia are at greater risk for side effects. Talk with your provider about this.

This medicine can cause drowsiness, dizziness, and problems with judgment. Do not drive or operate machinery until you are fully alert.

While taking this medicine, avoid strenuous exercise, high temperatures, and dehydration. This medicine interferes with your body's ability to cool down, and you may become overheated.

Using this medicine for a long time may cause muscle spasms, twitching in the face and body, and uncontrolled tongue or jaw movement. Talk to your healthcare provider about this.

Do not drink alcohol while you are taking this medicine.

This medicine may increase the risk of developing diabetes, especially if you are overweight or have a family history of diabetes. If you have diabetes, this medicine may affect your blood sugar level and change the amount of insulin or other diabetes medicines you may need. Talk to your healthcare provider about this.

What are the possible side effects?

Along with its needed effects, your medicine may cause some unwanted side effects. Some side effects may be very serious. Some side effects may go away as your body adjusts to the medicine. Tell your healthcare provider if you have any side effects that continue or get worse.

Serious (report these to your healthcare provider right away): Thoughts of suicide, seizures, increased thirst, increased urination, extreme hunger, uncontrolled muscle movements, slurred speech, fever, sweating, confusion, weakness or numbness on one side of your body.

Other: Drowsiness, insomnia, agitation, headache, dizziness, nervousness, runny nose, anxiety, constipation, dry mouth, stomach upset, tremors or shaking, weight gain.

What products might interact with this medicine?

When you take this medicine with other medicines, it can change the way this or any of the other medicines work. Nonprescription medicines, vitamins, natural remedies, and certain foods may also interact. Using these products together might cause harmful side effects. Talk to your healthcare provider if you are taking:

  • ACE inhibitors such as benazepril (Lotensin), captopril (Capoten), enalapril (Vasotec), fosinopril (Monopril), lisinopril (Prinivil, Zestril), quinapril (Accupril), and ramipril (Altace)
  • alcohol
  • alpha blockers such as prazosin (Minipress) and doxazosin (Cardura)
  • beta blockers such as atenolol (Tenormin), acebutolol (Sectral), pindolol, metoprolol (Lopressor, Toprol XL), sotalol (Betapace), nadolol (Corgard), propranolol (Inderal), labetalol (Normodyne, Trandate), and carvedilol (Coreg)
  • calcium channel blockers such as nifedipine (Adalat, Procardia), isradipine (DynaCirc), felodipine (Plendil), verapamil (Calan, Isoptin), diltiazem (Cardizem), and nicardipine (Cardene)
  • carbamazepine (Tegretol)
  • cold and flu medicines, especially antihistamines such as diphenhydramine (Benadryl) and chlorpheniramine (Chlor-Trimeton)
  • fluvoxamine (Luvox)
  • levodopa/carbidopa (Sinemet)
  • proton pump inhibitors such as omeprazole (Prilosec), esomeprazole (Nexium), pantoprazole (Protonix), and lansoprazole (Prevacid)
  • rifampin (Rifadin, Rifamate)
  • sedatives such as phenobarbital (Solfoton), amobarbital (Amytal), zolpidem (Ambien), triazolam (Halcion), butabarbital (Butisol), and zaleplon (Sonata)
  • tranquilizers such as diazepam (Valium), meprobamate (Equanil), chlordiazepoxide (Librium), alprazolam (Xanax), and lorazepam (Ativan).

Keep a list of all your medicines (prescription, nonprescription, supplements, natural remedies, and vitamins) with you. Be sure that you tell all healthcare providers who treat you about all the products you are taking.

How should I store this medicine?

Store this medicine at room temperature. Keep the container tightly closed. Protect it from heat, high humidity, and bright light.


This advisory includes selected information only and may not include all side effects of this medicine or interactions with other medicines. Ask your healthcare provider or pharmacist for more information or if you have any questions.

Ask your pharmacist for the best way to dispose of outdated medicine or medicine you have not used. Do not throw medicine in the trash.

Keep all medicines out of the reach of children.

Do not share medicines with other people.

Developed by McKesson Corporation
Published by McKesson Corporation.
Last modified: 2007-10-24
Last reviewed: 2007-08-16
This content is reviewed periodically and is subject to change as new health information becomes available. The information is intended to inform and educate and is not a replacement for medical evaluation, advice, diagnosis or treatment by a healthcare professional.
Copyright © 2007 McKesson Corporation and/or one of its subsidiaries. All Rights Reserved.
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