Clozapine is a unique antipsychotic that has helped over 225,00 people with schizophrenia, schizoaffective disorder and bipolar disorder.  Clozapine is an important treatment option because it tends to help even when other medicines did not work.  Like other antipsychotics, clozapine helps take away voices and other frightening symptoms.  After recovery from these symptoms, clozapine helps people to stabilize their mood and regain their motivation and concentration.  These benefits have allowed many people to live independent lives for the first time.

Clozapine is the only medication proven to help people with schizophrenia who have not responded to antipsychotic medication.  It is also one of few medicines that reduces suicide attempts and self-injury.

Unlike other antipsychotics, clozapine has few or no side effects involving the muscles, such as restlessness, stiffness, shakiness, and cramps.  Clozapine can improve muscle problems, such as tardive dyskinesia, that are caused by other antipsychotics.

Patients treated with clozapine have reported the following positive effects (remember, not everyone will experience all of these improvements):

·         Ability to concentrate improves

·         Ability to enjoy previous activity returns

·         Improved relationships

·         Ability to participate in counseling, vocational training, or other activities of daily life improves

·         Ability to live independently improves

·         A decrease in suicidal behavior

With all these benefits, why doesn’t everyone with schizophrenia take clozapine?  The answer is that clozapine can cause a serious side effect called “agranulocytosis,” which means a loss of the white blood cells that fight infection.  This problem is very rare, and happens in about 1 in 100 people who take clozapine. To help prevent it, people taking clozapine need to have their blood drawn regularly to check the white blood count.

How should this medicine be used?

Clozapine comes as a tablet to take by mouth. It usually is taken one to three times a day. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take clozapine exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.

The amount of clozapine you take may need to be adjusted, especially during the first few weeks. You will have weekly blood tests while taking clozapine and for 4 weeks after stopping it. Initially, you will receive only a 1-week supply of this medication at a time.

Continue to take clozapine even if you feel well. Do not stop taking clozapine without talking to your doctor, especially if you have taken large doses for a long time. Your doctor probably will want to decrease your dose gradually. This drug must be taken regularly for a few weeks before its full effect is felt.

What special precautions should I follow?

Before taking clozapine,

·         tell your doctor and pharmacist if you are allergic to clozapine or any other drugs.

·         tell your doctor and pharmacist what prescription and nonprescription medications you are taking, especially those listed in the IMPORTANT WARNING section, anticoagulants ('blood thinners') such as warfarin (Coumadin), benztropine (Cogentin), carbamazepine (Tegretol), cimetidine (Tagamet), dicyclomine (Bentyl), erythromcyin (E.E.S., E-Mycin, others), medication for high blood pressure, phenytoin (Dilantin), pain relievers such as codeine, selective serotonin reuptake inhibitors (SSRIs) such as fluoxetine (Prozac, Sarafem) and fluvoxamine (Luvox), trihexyphenidyl (Artane), and vitamins.

·         in addition to the condition listed in the IMPORTANT WARNING section, tell your doctor if you have or have ever had blood disorders; heart, kidney, or liver disease; depression; epilepsy; problems with your urinary system or prostate; glaucoma; irregular heartbeat; problems with your blood pressure; or blood problems caused by clozapine.

·         tell your doctor if you are pregnant, plan to become pregnant, or are breast-feeding. If you become pregnant while taking clozapine, call your doctor.

·         if you are having surgery, including dental surgery, tell the doctor or dentist that you are taking clozapine.

·         you should know that this drug may make you drowsy.

·         remember that alcohol can add to the drowsiness caused by this drug.

·         tell your doctor if you use tobacco products. Cigarette smoking may decrease the effectiveness of this drug.


What side effects can I expect?

If you take clozapine several times a day, take the missed dose as soon as you remember it and take any remaining doses for that day at evenly spaced intervals. However, if you remember a missed dose when it is almost time for your next scheduled dose, skip the missed dose.

If you take clozapine once a day at bedtime and do not remember it until the next morning, skip the missed dose. Do not take a double dose to make up for a missed one.

Serious side-effects

As with any medication, certain side effects are associated with clozapine. Some of the side effects that have been reported when therapy is started disappear with time or after the healthcare professional adjusts the dosage. In some cases the side effects require treatment. The healthcare professional, or another member of the treatment team, can give advice on how to recognize potential side effects and what to do about them.

In addition to agranulocytosis (the most serious side effect associated with clozapine), the following side effects have been reported:

Seizures or convulsions: The higher the dosage, the greater the risk of seizures. Also, people who have had seizures in the past are more likely to have them with clozapine. If a person suffers a seizure, he or she should tell their healthcare professional at once.

Fast or irregular heartbeat: If this happens, the dosage may be reduced, or this side effect may be treated with another medication.

Myocarditis (an inflammation of a muscle in the heart): The risk is greatest during the first month of clozapine therapy.

Orthostatic hypotension (a fall in blood pressure when suddenly standing up): The risk is highest when treatment with clozapine is started.

Other less serious reported side effects are drowsiness, heavy drooling, headache, constipation, fever, fatigue, nausea, and weight gain. Because healthcare professionals are familiar with these and other possible side effects, they can offer advice on relieving them.

Although side effects from clozapine are not common, they can occur. Tell your doctor if any of these symptoms are severe or do not go away:

·         drowsiness

·         dry mouth

·         weight gain

·         excessive saliva production

·         diarrhea

·         constipation

·         restlessness

·         headache

If you experience any of the following symptoms or those listed in the IMPORTANT WARNINGS section, call your doctor immediately:

·         tremor

·         seizures or convulsions

·         difficulty urinating or loss of bladder control

·         confusion

·         eye pain

·         shakiness

·         chest pain

·         severe muscle stiffness

·         sore throat

·         unusual bleeding or bruising

·         upset stomach

·         vomiting

·         loss of appetite

·         yellowness of the skin or eyes

Clozapine can cause high blood sugar (hyperglycemia). If you experience any of the following symptoms, call us:

·         thirst

·         dry mouth

·         tiredness

·         flushing

·         dry skin

·         frequent urination

·         loss of appetite

·         trouble breathing


What storage conditions are needed for this medicine?

Keep this medication in the container it came in, tightly closed, and out of reach of children. Store it at room temperature and away from excess heat and moisture (not in the bathroom). Throw away any medication that is outdated or no longer needed. Talk to your pharmacist about the proper disposal of your medication.

In case of emergency/overdose

In case of overdose, call your local poison control center at 1-800-222-1222. If the victim has collapsed or is not breathing, call local emergency services at 911.