What Is Clozaril Used For?

Clozaril contains clozapine and belongs to a group of medicines called antipsychotics. It helps correct chemical imbalances in the brain that may cause mental illness.

Primary Uses

Clozaril is used to treat schizophrenia, a mental illness with disturbances in thinking, feelings and behavior. It is only used when other antipsychotic medicines have not worked or have caused severe side effects.

How It Works

Clozaril works by correcting chemical imbalances in the brain which may cause mental illness.

How to Take Clozaril

Take Clozaril exactly as prescribed by your doctor. The dose will be started low and gradually increased to find the right amount for you.

Dosage Instructions

The usual starting dose is half of a 25 mg tablet once or twice on the first day. The dose is usually increased to one 25 mg tablet once or twice on the second day. After that, the dose can be slowly increased until the desired effect is achieved. Usually the total amount needed each day will be between 200 mg and 450 mg, but some people will need higher doses. The total daily amount is usually divided into 2 doses (morning and bedtime), but if your total dose is 200 mg or less, your doctor may allow you to take the whole amount at once, usually in the evening.

What If You Miss a Dose?

If you miss your dose and it is almost time for your next dose (within 4 hours), skip the missed dose and take your next dose when you are meant to. Otherwise, take it as soon as you remember, then go back to taking it as you would normally. If you have forgotten to take Clozaril for more than 2 days, do not start taking it again before you contact your doctor.

Available Tablet Strengths

Side Effects

Like all medications, this medicine can cause side effects. Most are mild and temporary, but some require medical attention.

Common Side Effects

These side effects occur relatively frequently and usually don’t require emergency care:

• Constipation or fewer bowel movements than normal
• Abdominal pain
• Nausea (feeling sick)
• Vomiting
• Stomach discomfort especially after meals
• Diarrhea
• Dry mouth

Important Warnings

Clozaril has serious warnings that require careful monitoring and immediate medical attention for certain symptoms.

Who Should Not Take Clozaril

Do not use if you are allergic to clozapine or any ingredients; have a low white blood cell count or previously had one caused by medicine (except following cancer treatment); are unable to have regular blood tests; are unconscious, in a coma, or have acute mental illness caused by alcohol or drugs; have blood diseases causing reduced red blood cells or platelets; have active liver disease or severe liver disease; have severe kidney disease; have myocarditis or other heart problems; have uncontrolled epilepsy; have paralytic ileus; have severe constipation or bowel obstruction; have bone marrow disease; or have problems with alcohol or drug abuse.

Medical Conditions to Discuss

Tell your doctor if you have: heart disease or family history of heart disease; family history of prolonged QT interval; stroke; neuroleptic malignant syndrome; tardive dyskinesia; liver or kidney problems; glaucoma; prostate problems; controlled epilepsy; diabetes or family history of diabetes; chronic constipation; dementia; or any other serious medical condition.

Pregnancy and Breastfeeding

Experience with Clozaril in pregnancy is very limited. If you need to take this medicine during pregnancy, your doctor will discuss the benefits and risks. Newborn babies of mothers taking antipsychotic drugs during the third trimester may have increased risk of developing stiff limbs, trembling, agitation, muscle problems, drowsiness, breathing problems, and feeding disorders. You should not breastfeed during Clozaril treatment as this medicine may pass into breast milk.

Drug Interactions

Some medicines may interfere with Clozaril and affect how it works. Tell your doctor about all medicines you are taking.

• Medicines that decrease blood cell production
• Other antipsychotic medicines
• Medicines for depression or mood swings
• Benzodiazepines and sleep medicines
• Epilepsy medicines (phenytoin, carbamazepine, valproic acid)
• Warfarin (blood thinner)
• Strong pain killers like morphine
• St John’s wort
• Antihistamines for colds or allergies
• Anticholinergic medicines for stomach cramps
• Parkinson’s disease medicines
• High blood pressure medicines
• Digoxin for heart problems
• Medicines for irregular heartbeat
• Stomach ulcer medicines (cimetidine, omeprazole, pantoprazole, lansoprazole)
• Antibiotics (erythromycin, clarithromycin, azithromycin, ciprofloxacin, norfloxacin, rifampicin)
• Antifungal or antiviral medicines
• Nicotine replacement products
• Atropine
• Adrenaline
• Birth control pills

Alcohol & Driving

Clozaril can affect your ability to drive and may interact dangerously with alcohol. It can also affect your body’s temperature regulation.

Alcohol

You should not drink alcohol while taking Clozaril. Tell your doctor if you drink alcohol.

Driving and Operating Machinery

Be careful before you drive or use any machines or tools until you know how Clozaril affects you. Clozaril can cause sleepiness and may increase drowsiness caused by other medicines.

Temperature Regulation

Clozaril may make you sweat less, causing your body to overheat. Be careful if you will be in a hot environment or do vigorous exercise.

Storage

Keep your tablets in a cool dry place where the temperature stays below 30°C. Keep it where children cannot reach it.

Overdose Information

If you think you have used too much Clozaril, you may need urgent medical attention. Immediately phone the Poisons Information Centre (Australia telephone 13 11 26) for advice, contact your doctor, or go to the Emergency Department at your nearest hospital. Do this even if there are no signs of discomfort or poisoning. The most common symptoms of overdose include light headedness due to low blood pressure, too much saliva, difficulty breathing, fast or irregular heartbeat, drowsiness, confusion and unconsciousness.

Frequently Asked Questions