Generic name: Clozapine Tablets [ KLOE-za-peen ]
Brand name: Clozaril
Drug class: Atypical antipsychotics

Medically reviewed by Drugs.com. Last updated on Oct 9, 2023.

Uses of Clozapine Tablets:

• It is used to treat schizophrenia.
• It is used to treat problems with how one acts.
• It may be given to you for other reasons. Talk with the doctor.

What do I need to tell my doctor BEFORE I take Clozapine Tablets?

• If you are allergic to this medicine (clozapine tablets); any part of this medicine (clozapine tablets); or any other drugs, foods, or substances. Tell your doctor about the allergy and what signs you had.
• If you have a low white blood cell count.
• If you have bone marrow disease.
• If you have any of these health problems: Low potassium or magnesium levels.
• If you have ever had a low white blood cell count when taking a drug before.
• If you are taking any drugs that can stop your bone marrow from making some of the cells that your body needs. There are many drugs that can do this. Ask your doctor or pharmacist if you are not sure.
• If you are not able to get blood tests as you have been told by your doctor.
• If you are breast-feeding. Do not breast-feed while you take this medicine (clozapine tablets).

This is not a list of all drugs or health problems that interact with this medicine (clozapine tablets).

Tell your doctor and pharmacist about all of your drugs (prescription or OTC, natural products, vitamins) and health problems. You must check to make sure that it is safe for you to take this medicine (clozapine tablets) with all of your drugs and health problems. Do not start, stop, or change the dose of any drug without checking with your doctor.

Related/similar drugs

quetiapine, aripiprazole, Abilify, Seroquel, olanzapine, risperidone

What are some things I need to know or do while I take Clozapine Tablets?

• Tell all of your health care providers that you take this medicine (clozapine tablets). This includes your doctors, nurses, pharmacists, and dentists.
• Avoid driving and doing other tasks or actions that call for you to be alert until you see how this medicine (clozapine tablets) affects you.
• To lower the chance of feeling dizzy or passing out, rise slowly if you have been sitting or lying down. Be careful going up and down stairs.
• High blood sugar or diabetes, high cholesterol, and weight gain have happened with drugs like this one. These may raise the chance of heart and brain blood vessel disease.
• If you have high blood sugar (diabetes), you will need to watch your blood sugar closely. Tell your doctor if you get signs of high blood sugar like confusion, feeling sleepy, more thirst, more hungry, passing urine more often, flushing, fast breathing, or breath that smells like fruit.
• Call your doctor right away if you have any signs of infection like fever, chills, flu-like signs, very bad sore throat, ear or sinus pain, cough, more sputum or change in color of sputum, pain with passing urine, mouth sores, or a wound that will not heal.
• An unsafe heartbeat that is not normal (long QT on ECG) has happened with this medicine (clozapine tablets). Chest pain, heart attack, and sudden deaths have also rarely happened in people taking this medicine (clozapine tablets). Talk with the doctor.
• Blood clots have happened with this medicine (clozapine tablets). Tell your doctor if you have ever had a blood clot. Talk with your doctor.
• Talk with your doctor before you drink alcohol or use other drugs and natural products that slow your actions.
• Be careful in hot weather or while being active. Drink lots of fluids to stop fluid loss.
• Dizziness, sleepiness, and feeling less stable may happen with this medicine (clozapine tablets). These may lead to falling, which can cause broken bones or other health problems.
• Very bad and sometimes deadly liver problems have happened with this medicine (clozapine tablets). Call your doctor right away if you have signs of liver problems like dark urine, feeling tired, not hungry, upset stomach or stomach pain, light-colored stools, throwing up, or yellow skin or eyes.
• Older adults with dementia taking drugs like this one have had a higher number of strokes. Sometimes these have been deadly. This medicine is not approved to treat mental problems caused by dementia.
• If you are 60 or older, use this medicine (clozapine tablets) with care. You could have more side effects.
• Tell your doctor if you are pregnant or plan on getting pregnant. You will need to talk about the benefits and risks of using this medicine (clozapine tablets) while you are pregnant.
• Taking this medicine (clozapine tablets) in the third trimester of pregnancy may lead to uncontrolled muscle movements and withdrawal in the newborn.

How is this medicine (Clozapine Tablets) best taken?

Use this medicine (clozapine tablets) as ordered by your doctor. Read all information given to you. Follow all instructions closely.

• Take with or without food.
• Keep taking this medicine (clozapine tablets) as you have been told by your doctor or other health care provider, even if you feel well.
• Have blood work checked as you have been told by the doctor. Talk with the doctor.
• You will need to have heart function tests while taking this medicine (clozapine tablets). Talk with the doctor.
• Do not stop taking this medicine (clozapine tablets) all of a sudden without calling your doctor. You may have a greater risk of signs of withdrawal. If you need to stop this medicine (clozapine tablets), you will want to slowly stop it as ordered by your doctor.
• If you start or stop smoking, talk with your doctor. How much drug you take may need to be changed.
• Tell your doctor if you use caffeine products (for example, tea, coffee, cola) and chocolate. How much of this medicine (clozapine tablets) you take may need to be changed.
• This medicine can cause very bad stomach or bowel problems like very bad constipation or bowel block. Sometimes, this has been deadly. To help avoid these problems, drink lots of noncaffeine liquids unless told to drink less liquid by your doctor. Laxatives may also help. Talk with your doctor.

What do I do if I miss a dose?

• Take a missed dose as soon as you think about it.
• If it is close to the time for your next dose, skip the missed dose and go back to your normal time.
• Do not take 2 doses at the same time or extra doses.
• If you miss 2 or more days of this medicine (clozapine tablets), call your doctor to find out how to restart.

What are some side effects that I need to call my doctor about right away?

WARNING/CAUTION: Even though it may be rare, some people may have very bad and sometimes deadly side effects when taking a drug. Tell your doctor or get medical help right away if you have any of the following signs or symptoms that may be related to a very bad side effect:

• Signs of an allergic reaction, like rash; hives; itching; red, swollen, blistered, or peeling skin with or without fever; wheezing; tightness in the chest or throat; trouble breathing, swallowing, or talking; unusual hoarseness; or swelling of the mouth, face, lips, tongue, or throat.
• Signs of high or low blood pressure like very bad headache or dizziness, passing out, or change in eyesight.
• Shakiness, trouble moving around, or stiffness.
• Weakness on 1 side of the body, trouble speaking or thinking, change in balance, drooping on one side of the face, or blurred eyesight.
• Swelling, warmth, numbness, change of color, or pain in a leg or arm.
• Coughing up blood.
• Blue or very pale skin in the arms or legs.
• Seizures.
• Feeling very tired or weak.
• Slow heartbeat.
• Change in eyesight.
• Hard or dry stools; bowel movements that are not as often as normal; severe constipation; stomach pain, bloating, or swelling; trouble passing gas; or upset stomach or throwing up.
• A very bad and sometimes deadly health problem called neuroleptic malignant syndrome (NMS) may happen. Call your doctor right away if you have any fever, muscle cramps or stiffness, dizziness, very bad headache, confusion, change in thinking, fast heartbeat, heartbeat that does not feel normal, or are sweating a lot.
• Some people may get a severe muscle problem called tardive dyskinesia. This problem may lessen or go away after stopping this medicine (clozapine tablets), but it may not go away. The risk is greater with diabetes and in older adults, especially older women. The risk is greater with longer use or higher doses, but it may also occur after short-term use with low doses. Call your doctor right away if you have trouble controlling body movements or problems with your tongue, face, mouth, or jaw like tongue sticking out, puffing cheeks, mouth puckering, or chewing.

What are some other side effects of Clozapine Tablets?

All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call your doctor or get medical help if any of these side effects or any other side effects bother you or do not go away:

• Dizziness or headache.
• Feeling sleepy.
• Constipation.
• Dry mouth.
• Weight gain.
• Trouble sleeping.
• More saliva.
• Sweating a lot.

These are not all of the side effects that may occur. If you have questions about side effects, call your doctor. Call your doctor for medical advice about side effects.

You may report side effects to the FDA at 1-800-332-1088. You may also report side effects at https://www.fda.gov/medwatch.

If OVERDOSE is suspected:

If you think there has been an overdose, call your poison control center or get medical care right away. Be ready to tell or show what was taken, how much, and when it happened.

How do I store and/or throw out Clozapine Tablets?

• Store at room temperature. Do not refrigerate or freeze.
• Store in a dry place. Do not store in a bathroom.
• Protect from light.
• Keep all drugs in a safe place. Keep all drugs out of the reach of children and pets.
• Throw away unused or expired drugs. Do not flush down a toilet or pour down a drain unless you are told to do so. Check with your pharmacist if you have questions about the best way to throw out drugs. There may be drug take-back programs in your area.

Consumer Information Use and Disclaimer

• If your symptoms or health problems do not get better or if they become worse, call your doctor.
• Do not share your drugs with others and do not take anyone else's drugs.
• Some drugs may have another patient information leaflet. Check with your pharmacist. If you have any questions about this medicine (clozapine tablets), please talk with your doctor, nurse, pharmacist, or other health care provider.
• If you think there has been an overdose, call your poison control center or get medical care right away. Be ready to tell or show what was taken, how much, and when it happened.

Further information

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

Medical Disclaimer