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What You Should Know About Clozapine

What is clozapine

Clozapine is an antipsychotic medicine used to treat symptoms of schizophrenia. It may work better than other medicines.

Clozapine may help you:

  • Think more clearly

  • Control your thoughts and mood

  • Communicate better

  • Feel better

Clozapine is used:

If your symptoms were not helped by other antipsychotic medicines - OR - If you experienced side effects from other medicines that caused you to stop taking them.

How good is clozapine?

In patients who have tried and failed other antipsychotics, clozapine worked better. 

Clozapine can be very helpful in controlling these symptoms:

  • Feeling suspicious

  • Hearing voices that others do not hear

  • Seeing things that others do not see

  • Uncontrolled anger and hostility

  • Lack of drive

  • Feeling depressed

  • Not taking care of yourself, not bathing

  • Not able to relate to others

Everyone responds differently

Clozapine may not help everyone. You may respond to treatment in a few weeks or months. Some patients say they continue to see improvement up to one year or more after starting clozapine. 

Image of a couple sitting down and talking with their healthcare provider.

What are the side effects of clozapine?

Rare, but severe side effects:

  • Low white blood cell count

  • Seizures—dose related; more risk if you have a history of seizures

  • Heart muscle problems—flu-like symptoms, shortness of breath 

Tell your provider right away if you have any severe side effects.

Other side effects with clozapine and other antipsychotics:

  • Feeling sleepy

  • Feeling dizzy

  • Drooling

  • Weight gain

  • Low blood pressure

  • Increased heart rate

  • Constipation

  • High cholesterol

  • High blood sugar

Your healthcare providers can work with you to help manage these side effects.

Clozapine can increase your cholesterol and blood sugar, and in rare cases, lower your white blood cells. For your safety, you will need to go to the lab and have blood tests. By law, the pharmacy may not fill your clozapine without the blood test.


Test once a week for the first 6 months


Test once every 2 weeks for the next 6 months


Test once every 4 weeks

We are here to help answer your questions. Taking clozapine is your choice.

Author: StayWell Custom Communications
Last Annual Review Date: 2/1/2017
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