Clozapine

Clozapine is an atypical antipsychotic medication that is used to treat schizophrenia. The medication works by blocking or lessening the effects of certain chemicals in the brain that can become elevated in people with schizophrenia. Clozapine is usually reserved for people who have failed to respond to other schizophrenia medications. It comes in tablet form, and is generally taken one to three times per day.

What Is Clozapine?

Clozapine (Clozaril®, FazaClo®) is a prescription medication that is used to treat schizophrenia in people who have failed to respond to other schizophrenia medications. It is also approved to decrease the risk of recurrent suicidal behavior in people with schizophrenia or schizoaffective disorder.
 

Who Makes Clozapine?

It is manufactured by Novartis Pharmaceuticals.
 
(Click What Is Clozapine Used For? to learn more, including possible off-label uses for the drug.)
 

How Does It Work?

Clozapine belongs to a group of medications called atypical (or second-generation) antipsychotic medications. It is not entirely clear how the drug works in the treatment of schizophrenia. However, it is known that clozapine blocks or lessens the effects of several chemicals in the brain. These chemicals (such as dopamine and serotonin) may be elevated in people with schizophrenia.
 
This drug is not a cure for schizophrenia, however. It only helps to control symptoms (see Symptoms of Schizophrenia).
 

When and How to Take Clozapine

The following are some general considerations for when and how to take the medication:
 
  • Clozapine comes in tablet form. It is usually taken by mouth one to three times daily.
     
  • You can take it with or without food. If the medication bothers your stomach, try taking it with food.
     
  • It should be taken at the same time(s) each day to maintain an even level in your blood.
     
  • For the drug to work properly, it must be taken as prescribed. It will not work if you stop taking it.
 

Dosing Information

The dosage that your healthcare provider recommends will vary, depending on a number of factors, including:
 
  • Other medical conditions you may have
  • Other medications you may currently be taking.
     
As with any medication, do not adjust your dose unless your healthcare provider specifically instructs you to do so.
 
(Click Clozapine Dosing for more information.)
 

Side Effects

As with any medicine, side effects are possible with clozapine. However, not everyone who takes it will experience side effects. In fact, most people tolerate the medication quite well. If side effects do occur, in most cases, they are minor and either require no treatment or can easily be treated by you or your healthcare provider. Serious side effects are less common.
 
Common side effects of clozapine include, but are not limited to:
 
(Click Clozapine Side Effects to learn more, including potentially serious side effects that you should report immediately to your healthcare provider.)
 
You can also read about specific side effects of the drug in the following eMedTV articles:
 
 

Drug Interactions With Clozapine

Clozapine can potentially interact with a number of other medicines (see Drug Interactions With Clozapine).
 

What Should I Tell My Healthcare Provider?

You should talk with your healthcare provider prior to taking this medication if you have:
 
Also let your healthcare provider know if you are:
 
You should also tell your healthcare provider about all of the medicines you take, including prescription and non-prescription medicines, vitamins, and herbal supplements.
 
(Click Precautions and Warnings With Clozapine to learn more, including information on who should not take the drug.)
 

What If I Take an Overdose?

People who take too much clozapine may have overdose symptoms that could include:
 
  • Drowsiness
  • Delirium
  • Coma
  • A rapid heart rate (tachycardia)
  • Low blood pressure (hypotension)
  • Difficulty breathing
  • Increased salivation
  • Pneumonia
  • An irregular heart rhythm (arrhythmia)
  • Loss of life.
     
If you happen to overdose, seek immediate medical attention.
 
(Click Clozapine Overdose for more information.)
 

How Should It Be Stored?

Clozapine should be stored at room temperature, away from moisture and heat. The tablets should be stored in an airtight container.
 
Keep clozapine and all other medications out of the reach of children.
 

What Should I Do If I Miss a Dose?

If you do not take your clozapine as scheduled, take your missed dose as soon as you remember. If it is almost time for your next dose, skip the missed dose and continue with your regular schedule. Do not take a double dose.
 

Strengths of Clozapine

Clozapine tablets are available in the following strengths:
 
  • Clozapine 25 mg
  • Clozapine 100 mg.
     
Generic clozapine is available in the above strengths, as well as clozapine 50 mg tablets.
 

Alternatives

There are several alternatives to clozapine for the treatment of schizophrenia. Other atypical antipsychotic medications used for schizophrenia include:
 
Older, "typical" antipsychotics are also approved to treat schizophrenia. Haloperidol (Haldol®) and thioridazine (Mellaril®) are examples of typical antipsychotics.
 
(Click Clozapine Alternatives for more information, including non-medication alternatives to clozapine.)
 

Generic Clozapine

Currently, both brand-name and generic clozapine are licensed for sale (see Generic Clozaril).
Written by/reviewed by: Kristi Monson, PharmD; Arthur Schoenstadt, MD
Last reviewed by: Kristi Monson, PharmD;
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