This information from Lexicomp® explains what you need to know about this medication, including what it’s used for, how to take it, its side effects, and when to call your healthcare provider.
Brand Names: US
Clozaril; Versacloz
Brand Names: Canada
AA-Clozapine; Clozaril; GEN-Clozapine
Warning
- This drug may lower the ability of the bone marrow to make white blood cells. This can lead to severe and sometimes deadly infections. Your child will need to have blood work checked before starting, during, and after treatment is stopped. Do what the doctor tells you about blood tests while your child is taking this drug.
- This drug may cause seizures in some people. The chance of seizures may be higher with higher doses or if your child has ever had seizures. The chance may also be higher if your child takes other drugs that may raise the risk of seizures, has a health problem that raises the risk of seizures, or in some patients who drink alcohol. Have your child use care when doing tasks or actions (like climbing and swimming) that may not be safe for your child or others if your child were to pass out.
- This drug may raise the chance of a very bad and sometimes deadly heart problem (myocarditis). Most of the time, these heart problems have happened within the first 2 months of care but may happen at anytime. Call the doctor right away if your child has a big weight gain, an abnormal heartbeat, chest pain or pressure, a fast heartbeat, fever, flu-like signs, shortness of breath, swelling in the arms or legs, or severe dizziness or passing out.
- Low blood pressure, passing out, slow heartbeat, and other severe heart problems have happened with this drug. These problems can be deadly. The chance of these problems is highest when this drug is first started. It may also be higher if the drug is stopped and restarted. Do not give your child more than you were told or raise your child’s dose faster than you were told. Tell the doctor if your child has heart or blood vessel problems, including problems with blood vessels in the brain. Tell the doctor if your child is dehydrated, has fluid loss, or takes drugs for high blood pressure.
- There is a higher chance of death in older adults who take this drug for mental problems caused by dementia. Most of the deaths were linked to heart disease or infection. This drug is not approved to treat mental problems caused by dementia.
What is this drug used for?
- It is used to treat problems with how one acts.
- It is used to treat schizophrenia.
- It may be given to your child for other reasons. Talk with the doctor.
What do I need to tell the doctor BEFORE my child takes this drug?
- If your child is allergic to this drug; any part of this drug; or any other drugs, foods, or substances. Tell the doctor about the allergy and what signs your child had.
- If your child has any of these health problems: Low potassium levels, low magnesium levels, or low white blood cell count.
- If your child has bone marrow disease, talk with the doctor.
- If your child has ever had a low white blood cell count when taking a drug before.
- If your child is taking any drugs that stop the bone marrow from making some of the cells that the body needs. There are many drugs that can do this. Ask the doctor or pharmacist if you are not sure.
- If your child is not able to get blood tests as you have been told by your child’s doctor.
This is not a list of all drugs or health problems that interact with this drug.
Tell the doctor and pharmacist about all of your child’s drugs (prescription or OTC, natural products, vitamins) and health problems. You must check to make sure that it is safe to give this drug with all of your child’s other drugs and health problems. Do not start, stop, or change the dose of any drug your child takes without checking with the doctor.
What are some things I need to know or do while my child takes this drug?
- Tell all of your child’s health care providers that your child is taking this drug. This includes your child’s doctors, nurses, pharmacists, and dentists.
- Have your child avoid tasks or actions that call for alertness until you see how this drug affects your child. These are things like riding a bike, playing sports, or using items such as scissors, lawnmowers, electric scooters, toy cars, or motorized vehicles.
- To lower the chance of feeling dizzy or passing out, have your child rise slowly if your child has been sitting or lying down. Have your child be careful going up and down stairs.
- Have your child’s blood work and heart function checked as you have been told by the doctor.
- If your child has phenylketonuria (PKU), talk with your child’s doctor. Some products have phenylalanine.
- 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 your child has high blood sugar (diabetes), you will need to watch your child’s blood sugar closely.
- Do not stop giving this drug to your child all of a sudden without calling the doctor. Your child may have a greater risk of signs of withdrawal. If your child needs to stop this drug, you will want to slowly stop it as ordered by the doctor.
- Alcohol may interact with this drug. Be sure your child does not drink alcohol.
- Talk with your child’s doctor before your child uses marijuana, other forms of cannabis, or prescription or OTC drugs that may slow your child’s actions.
- If your child smokes or will be stopping smoking, talk with the doctor. How much drug your child takes may need to be changed.
- Tell the doctor if your child uses caffeine products like tea, coffee, cola, and chocolate. How much drug your child takes may need to be changed.
- Have your child be careful in hot weather or while your child is being active. Have your child drink lots of fluids to stop fluid loss.
- Dizziness, sleepiness, and feeling less stable may happen with this drug. These may lead to falling, which can cause broken bones or other health problems.
- An unsafe heartbeat that is not normal (long QT on ECG) has happened with this drug. Chest pain, heart attack, and sudden deaths have also rarely happened in people taking this drug. Talk with the doctor.
- Blood clots have happened with this drug. Tell the doctor if your child has ever had a blood clot.
- This drug 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, have your child drink lots of noncaffeine liquids unless told to drink less liquid by the doctor. Laxatives may also help. Talk with your child’s doctor.
If your child is pregnant or breast-feeding a baby:
- Talk with the doctor if your child is pregnant, becomes pregnant, or is breast-feeding a baby. You will need to talk about the benefits and risks to your child and the baby.
- Taking this drug in the third trimester of pregnancy may lead to side effects or withdrawal in the newborn.
- If your child is breast-feeding a baby, the doctor will need to watch your child’s baby for certain side effects.
What are some side effects that I need to call my child’s 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 child’s doctor or get medical help right away if your child has 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 infection like fever, chills, very bad sore throat, ear or sinus pain, cough, more sputum or change in color of sputum, pain with passing urine, mouth sores, or wound that will not heal.
- Signs of high blood sugar like confusion, feeling sleepy, unusual thirst or hunger, passing urine more often, flushing, fast breathing, or breath that smells like fruit.
- 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.
- Seizures.
- Feeling very tired or weak.
- Change in eyesight.
- Passing urine more often.
- 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.
- Call the doctor right away if your child has signs of a blood clot like chest pain or pressure; coughing up blood; shortness of breath; swelling, warmth, numbness, change of color, or pain in a leg or arm; or trouble speaking or swallowing.
- Liver problems have happened with this drug. Sometimes, these have been deadly. Call the doctor right away if your child has signs of liver problems like dark urine, tiredness, decreased appetite, upset stomach or stomach pain, light-colored stools, throwing up, or yellow skin or eyes.
- A very bad and sometimes deadly health problem called neuroleptic malignant syndrome (NMS) may happen. Call your child’s doctor right away if your child has any fever, muscle cramps or stiffness, dizziness, very bad headache, confusion, change in thinking, fast heartbeat, heartbeat that does not feel normal, or is sweating a lot.
- Some people may get a severe muscle problem called tardive dyskinesia. This problem may lessen or go away after stopping this drug, but it may not go away. The risk is greater with diabetes and in older adults, especially older females. The risk is greater with longer use or higher doses, but it may also occur after short-term use with low doses. Call your child’s doctor right away if your child has trouble controlling body movements or problems with the tongue, face, mouth, or jaw like tongue sticking out, puffing cheeks, mouth puckering, or chewing.
What are some other side effects of this drug?
All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call your child’s doctor or get medical help if any of these side effects or any other side effects bother your child or do not go away:
- Dizziness or headache.
- Feeling sleepy.
- Constipation.
- Dry mouth.
- Upset stomach or throwing up.
- Heartburn.
- 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 child’s doctor. Call your child’s doctor for medical advice about side effects.
You may report side effects to your national health agency.
How is this drug best given?
Give this drug as ordered by your child’s doctor. Read all information given to you. Follow all instructions closely.
All products:
- Give this drug with or without food.
- Keep giving this drug to your child as you have been told by your child’s doctor or other health care provider, even if your child feels well.
Oral-disintegrating tablet:
- Do not push the tablet out of the foil when opening. Use dry hands to take it from the foil. Place on your child’s tongue and let it dissolve. Water is not needed. Do not let your child swallow it whole. Your child may chew the tablet.
Liquid (suspension):
- Shake well before use.
- Measure liquid doses carefully. Use the measuring device that comes with this drug.
- Do not draw into a syringe and store for future use.
What do I do if my child misses a dose?
- Give a missed dose as soon as you think about it.
- If it is close to the time for your child’s next dose, skip the missed dose and go back to your child’s normal time.
- Do not give 2 doses or extra doses.
- If your child misses 1 day or more of this drug, your child may need to restart at a lower dose to lower the risk of side effects. Call the doctor to find out how to restart.
How do I store and/or throw out this drug?
All products:
- 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.
Oral-disintegrating tablet:
- Store in pouch until ready for use.
- Give oral-disintegrating tablet right after opening. Throw away any part of opened pouch that is not used.
Liquid (suspension):
- Throw away any part not used 100 days after opening the first time.
General drug facts
- If your child’s symptoms or health problems do not get better or if they become worse, call your child’s doctor.
- Do not share your child’s drug with others and do not give anyone else’s drug to your child.
- Some drugs may have another patient information leaflet. If you have any questions about this drug, please talk with your child’s 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.
Consumer Information Use and Disclaimer
This generalized information is a limited summary of diagnosis, treatment, and/or medication information. It is not meant to be comprehensive and should be used as a tool to help the user understand and/or assess potential diagnostic and treatment options. It does NOT include all information about conditions, treatments, medications, side effects, or risks that may apply to a specific patient. It is not intended to be medical advice or a substitute for the medical advice, diagnosis, or treatment of a health care provider based on the health care provider’s examination and assessment of a patient’s specific and unique circumstances. Patients must speak with a health care provider for complete information about their health, medical questions, and treatment options, including any risks or benefits regarding use of medications. This information does not endorse any treatments or medications as safe, effective, or approved for treating a specific patient. UpToDate, Inc. and its affiliates disclaim any warranty or liability relating to this information or the use thereof. The use of this information is governed by the Terms of Use, available at https://www.wolterskluwer.com/en/know/clinical-effectiveness-terms.
Last Reviewed Date
2024-10-25
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