What is Clozaril?

Clozaril is a medication known as an atypical antipsychotic that is used to treat symptoms of schizophrenia when standard medications have failed.

When did the U.S. Food and Drug Administration (FDA) approve the medication?

Clozaril was first approved by the FDA to treat schizophrenia in 2015.


Is there a generic version of Clozaril?

Yes, the generic version is known as clozapine and is available in the United States.


Are there any major differences between Clozaril and other antipsychotics used to treat Clozaril?

Clozaril belongs to the class of medications known as atypical antipsychotics or second generation psychotics. Clozaril is usually prescribed when other antipsychotics fail to relieve symptoms or when a person with schizophrenia suffers from suicidal ideation, as there is a risk for lowered white blood cell count. Talk to your doctor about what might work best for you and the costs and benefits of taking the medication. Some people may need to try several different antipsychotics before they find the most effective with the fewest side effects.


Can children take Clozaril?

The effectiveness and safety of the medication has not been tested in patients less than 18 years old. Talk to your child’s doctor about the risks of using the medication.


Are there potential interaction issues for people taking Clolzaril and any other drugs?

There are hundreds of drugs which are known to interact with Clozaril in major, moderate, or mild ways, so let your doctor know what other medications you are taking before you begin taking the medication. Some of these include antihistamines, cimetidine, antibiotics, bupropion, escitalopram, blood pressure medications, nausea medications, medication for irregular heartbeat, oral contraceptives, seizure medication, St. John’s wort, sedatives, SSRIs, sleep medication, terbinafine, and tranquilizers.


Are there any other medical conditions that would make someone ineligible for Clozaril therapy?

Talk to your doctor about other medical conditions before you take Clozaril, such as dementia, stroke, heart conditions, seizures, neuroleptic malignant syndrome (NMS), diabetes, kidney or liver disease, or tardive dyskinesia.


What is the typical dose that would be prescribed to someone taking Clozaril?

Typical starting dosage for treating schizophrenia in adults is 12.5 mg taken once or twice daily and increased gradually. Dosage is not to exceed 900 mg per day.


What do I do if I miss a dose?

Take the dose of Clozaril when you remember, but skip the missed dose if it it’s almost time for your next dose. You should never take extra doses of the medication to make up for missed doses. If you haven’t taken the medication for more than 2 days, contact your doctor before taking it again, as you may need to begin medication again at a lower dosage.


What common side effects can Clozaril cause?

The common side effects of Clozaril can include:

  • drowsiness
  • increase in saliva
  • dry mouth
  • dizziness
  • headache
  • restlessness
  • constipation.


Report major side effects to your doctor immediately, which can include uncontrollable hand shaking, changes in vision, sweating, confusion, fainting, shakiness, muscle stiffness, loss of appetite, nausea, bleeding or bruising, yellowing of skin or eyes, difficulty urinating, loss of bladder control, stomach pain, fatigue, flu-like symptoms, or behavioral changes. You can also report side effects to the FDA at 1-800-FDA-1088 or online.


What are the potential long-term effects of taking Clozaril?

There is a great risk for lowered white blood cell count and for seizures when taking Clozaril, which is why the medication is only prescribed when standard treatments for schizophrenia are not effective. Your doctor should monitor for progression of potential long-term side effect of atypical antipsychotics, which can include tardive dyskinesia (TD). Atypical antipsychotics may also increase the risk of cardiovascular side effects, diabetes, weight gain, and high cholesterol.


Is it safe for a woman who is pregnant, about to become pregnant, or nursing to take Clozaril?

There have been no controlled human pregnancy studies on the effects of Clozaril. It is not known whether the drug can be transferred via human breast milk and harm a baby, but animal studies indicate the drug may be present in breast milk and potentially harm a nursing infant . Therefore, talk to your doctor if you are pregnant, planning to become pregnant, or are nursing before you take Clorazil.


Can symptoms occur if Clozaril is discontinued?

It’s important not to discontinue use of the drug if you feel better. Maintain contact with your doctor and seek medical attention if necessary when discontinuing the drug. Talk to your doctor about how to mitigate potential withdrawal symptoms, which can include nausea, vomiting, increased saliva, sweating, diarrhea, trouble sleeping, agitation, and onset of psychotic symptoms.


What should I do if I overdose on Clozaril?

Seek immediate help or call the Poison Help Line at 1-800-222-1222 if you overdose, as it can be fatal. Symptoms may include fainting, dizziness, changes in heartbeat, slowed breathing, and loss of consciousness, delirium, hypotension, tachycardia, increased saliva, and coma.


Is Clozaril habit-forming?
Clozaril has no habit-forming potential, but it is not recommended that you discontinue use of the drug before talking with your doctor, as withdrawal symptoms can occur.


How much does Clozaril cost?

According to goodrx.com, 90 tablets of 100 mg Clozaril cost approximately $1,200. 90 tablets of the 100 mg generic clozapine cost approximately $100.


Are there any disadvantages to Clozaril? 

The biggest disadvantages of Clozaril are the increased risk for lowered white blood cell count and seizures, and the other potential long-term side effects, which can include tardive dyskinesia, hyperglycemia, and weight gain.



DISCLAIMER: The information contained herein should NOT be used as a substitute for the advice of an appropriately qualified and licensed physician or other health care provider.  This article mentions drugs that were FDA-approved and available at the time of publication and may not include all possible drug interactions or all FDA warnings or alerts. The author of this page explicitly does not endorse this drug or any specific treatment method. If you have health questions or concerns about interactions, please check with your physician or go to the FDA site for a comprehensive list of warnings.




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Last Updated: Nov 25, 2018