What is this medication?
CLOZAPINE (KLOE za peen) treats schizophrenia. It is prescribed when other medications have not worked or cannot be tolerated. It works by balancing the levels of dopamine and serotonin in your brain, substances that help regulate mood. It belongs to a group of medications called antipsychotics.
This medicine may be used for other purposes; ask your health care provider or pharmacist if you have questions.
COMMON BRAND NAME(S): Clozaril
What should I tell my care team before I take this medication?
They need to know if you have any of these conditions:
- Blockage in your bowel
- Cigarette smoker
- Difficulty swallowing
- Have trouble controlling your muscles
- Heart disease
- High cholesterol
- History of irregular heartbeat
- History of stroke
- Kidney disease
- Liver disease
- Low blood counts, like low white cell, platelet, or red cell counts
- Low blood pressure
- Parkinson's disease
- Prostate disease
- Trouble passing urine
- An unusual or allergic reaction to clozapine, other medications, foods, dyes, or preservatives
- Pregnant or trying to get pregnant
How should I use this medication?
Take this medication by mouth with a glass of water. Follow the directions on the prescription label. This medication may be taken with or without food. Take your doses at regular intervals. Do not take your medication more often than directed. Do not suddenly stop taking this medication. You may need to gradually reduce the dose. Only stop taking this medication on the advice of your care team.
Talk to your care team about the use of this medication in children. Special care may be needed.
Overdosage: If you think you have taken too much of this medicine contact a poison control center or emergency room at once.
NOTE: This medicine is only for you. Do not share this medicine with others.
What if I miss a dose?
If you miss a dose, take it as soon as you can. If it is almost time for your next dose, take only that dose. Do not take double or extra doses. If you miss your medication for more than 2 days, you should not restart your medication at the same dose. Contact your care team for instructions.
What may interact with this medication?
Do not take this medication with any of the following:
- Dextromethorphan; quinidine
This medication may also interact with the following:
- Antihistamines for allergy, cough, and cold
- Certain antibiotics like ciprofloxacin, enoxacin, erythromycin, moxifloxacin
- Certain medications for anxiety or sleep
- Certain medications for bladder problems like oxybutynin, tolterodine
- Certain medications for cancer
- Certain medications for depression like amitriptyline, fluoxetine, sertraline
- Certain medications for fungal infection like fluconazole, itraconazole, ketoconazole, posaconazole
- Certain medications for irregular heart beat like amiodarone, dofetilide, encainide, flecainide, propafenone, sotalol
- Certain medications for stomach problems like dicyclomine, hyoscyamine
- Certain medications for travel sickness like scopolamine
- Estrogen or progestin hormones
- General anesthetics like halothane, isoflurane, methoxyflurane, propofol
- Levodopa or other medications for Parkinson disease
- Medications for blood pressure
- Medications for seizures
- Medications that lower your chance of fighting infection
- Medications that relax muscles
- Other medications that prolong the QT interval (cause an abnormal heart rhythm)
- Phenothiazines like perphenazine, prochlorperazine
- St. John's Wort
This list may not describe all possible interactions. Give your health care provider a list of all the medicines, herbs, non-prescription drugs, or dietary supplements you use. Also tell them if you smoke, drink alcohol, or use illegal drugs. Some items may interact with your medicine.
What should I watch for while using this medication?
Visit your care team for regular checks on your progress. Tell your care team if symptoms do not start to get better or if they get worse. Do not stop taking except on your care team's advice. You may develop a severe reaction. Your care team will tell you how much medication to take.
This medication may cause serious skin reactions. They can happen weeks to months after starting the medication. Contact your care team right away if you notice fevers or flu-like symptoms with a rash. The rash may be red or purple and then turn into blisters or peeling of the skin. Or, you might notice a red rash with swelling of the face, lips or lymph nodes in your neck or under your arms.
You must have a weekly blood test when you first begin this medication. If your blood counts stay in the right range, your tests may be reduced after 6 months to every other week. Your name will go on a national registry of patients who take this medication, to make sure that you have never had a serious reaction to it.
This medication can cause constipation. Talk to your care team if you have bowel movements less often than usual or if you have less than 3 bowel movements per week. Call if stool is hard or dry, or if you have trouble passing gas. Contact your care team right away if you have nausea, vomiting, or stomach swelling or pain. Drink plenty of water.
You may get drowsy or dizzy. Do not drive, use machinery, or do anything that needs mental alertness until you know how this medication affects you. Do not stand or sit up quickly, especially if you are an older patient. This reduces the risk of dizzy or fainting spells. Alcohol may interfere with the effect of this medication. Avoid alcoholic drinks.
Do not treat yourself for colds, fever, diarrhea, or allergies. Ask your care team for advice, some nonprescription medications may increase possible side effects.
This medication may increase blood sugar. Ask your care team if changes in diet or medications are needed if you have diabetes.
If you smoke, tell your care team if you notice this medication is not working well for you. Talk to your care team if you are a smoker or if you decide to stop smoking.
If you are going to have surgery tell your care team that you are taking this medication.
This medication can cause problems with controlling your body temperature. It can lower the response of your body to cold temperatures. If possible, stay indoors during cold weather. If you must go outdoors, wear warm clothes. It can also lower the response of your body to heat. Do not overheat. Do not over-exercise. Stay out of the sun when possible. If you must be in the sun, wear cool clothing. Drink plenty of water. If you have trouble controlling your body temperature, call your care team right away.
What side effects may I notice from receiving this medication?
Side effects that you should report to your care team as soon as possible:
- Allergic reactions—skin rash, itching, hives, swelling of the face, lips, tongue, or throat
- Anticholinergic toxicity—flushed face, dry mouth and skin, fast or irregular heartbeat, constipation
- Blood clot—pain, swelling, or warmth in the leg, shortness of breath, chest pain
- Constipation, bloating, nausea or vomiting, stomach pain, which may be signs of slow movement through the digestive tract
- Heart muscle inflammation—unusual weakness or fatigue, shortness of breath, chest pain, fast or irregular heartbeat, dizziness, swelling of the ankles, feet, or hands
- Heart rhythm changes—fast or irregular heartbeat, dizziness, feeling faint or lightheaded, chest pain, trouble breathing
- High blood sugar (hyperglycemia)—increased thirst or amount of urine, unusual weakness or fatigue, blurry vision
- High fever, stiff muscles, increased sweating, fast or irregular heartbeat, and confusion, which may be signs of neuroleptic malignant syndrome
- Infection—fever, chills, cough, or sore throat
- Liver injury—right upper belly pain, loss of appetite, nausea, light-colored stool, dark yellow or brown urine, yellowing skin or eyes, unusual weakness or fatigue
- Low blood pressure—dizziness, feeling faint or lightheaded, blurry vision
- Rash, fever, and swollen lymph nodes
- Stroke—sudden numbness or weakness of the face, arm, or leg, trouble speaking, confusion, trouble walking, loss of balance or coordination, dizziness, severe headache, change in vision
- Trouble passing urine
- Uncontrolled and repetitive body movements, muscle stiffness or spasms, tremors or shaking, loss of balance or coordination, restlessness, shuffling walk, which may be signs of extrapyramidal symptoms (EPS)
Side effects that usually do not require medical attention (report to your care team if they continue or are bothersome):
- Excessive drooling
- Weight gain
This list may not describe all possible side effects. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.
Where should I keep my medication?
Keep out of the reach of children.
Store at room temperature below 30 degrees C (86 degrees F). Throw away any unused medication after the expiration date.
NOTE: This sheet is a summary. It may not cover all possible information. If you have questions about this medicine, talk to your doctor, pharmacist, or health care provider.
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