clozapine

KLOE-za-peen

Oral route(Tablet;Tablet, Disintegrating)

Risks associated with the use of clozapine include agranulocytosis, seizures, myocarditis, orthostatic hypotension, and respiratory and/or cardiac arrest. Patients being treated with clozapine must have a baseline white blood cell (WBC) count and absolute neutrophil count (ANC) before initiation of treatment as well as regular WBC counts and ANCs during treatment and for at least 4 weeks after discontinuation of treatment. Clozapine is only available through a distribution system that ensures monitoring of WBC count and ANC according to the schedule prior to delivery of the next supply of medication. Elderly patients with dementia-related psychosis treated with atypical antipsychotic drugs are at an increased risk of death compared to placebo, Although the causes of death in clinical trials were varied, most appeared to be cardiovascular (eg, heart failure, sudden death) or infectious (eg, pneumonia) in nature. Not approved for the treatment of patients with dementia-related psychosis. Observational studies suggest that antipsychotic drugs may increase mortality. It is unclear from these studies to what extent the mortality findings may be attributed to the antipsychotic drug as opposed to patient characteristics. Clozapine is not approved for the treatment of patients with dementia-related psychosis .

Commonly used brand name(s)

In the U.S.

• Clozaril


• FazaClo

Available Dosage Forms:

• Tablet


• Tablet, Disintegrating

Therapeutic Class: Antipsychotic

Chemical Class: Dibenzodiazepine

Uses For clozapine

Clozapine is used to treat schizophrenia in patients who have not been helped by or are unable to take other medicines. clozapine should not be used to treat behavioral problems in older adult patients who have dementia.

Clozapine is also used to prevent risk of suicidal behavior from occurring again in patients with schizophrenia or schizoaffective disorder.

Clozapine is available only from pharmacies that agree to participate with your doctor in a plan to monitor your blood tests. You will need to have blood tests done every week for at least 6 months. After that, your doctor will decide if it is safe for you to have blood tests every other week. You will receive enough clozapine to last until your next blood test, but only if the results of your blood tests show that it is safe for you to take clozapine. If any of your blood tests are not normal, you may need to have blood tests more often than every week until they return to normal.

Before Using clozapine

In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For clozapine, the following should be considered:

Allergies

Tell your doctor if you have ever had any unusual or allergic reaction to clozapine or any other medicines. Also tell your health care professional if you have any other types of allergies, such as to foods, dyes, preservatives, or animals. For non-prescription products, read the label or package ingredients carefully.

Pediatric

Appropriate studies have not been performed on the relationship of age to the effects of clozapine in the pediatric population. Safety and efficacy have not been established.

Geriatric

Appropriate studies performed to date have not demonstrated geriatric-specific problems that would limit the usefulness of clozapine in the elderly. However, elderly patients are more likely to have constipation; trouble passing urine; uncontrolled movements; or age-related liver, kidney, or heart problems, which may require caution in patients receiving clozapine. clozapine should not be used for behavioral problems in older adults with dementia.

Pregnancy

	Pregnancy Category	Explanation
All Trimesters	B	Animal studies have revealed no evidence of harm to the fetus, however, there are no adequate studies in pregnant women OR animal studies have shown an adverse effect, but adequate studies in pregnant women have failed to demonstrate a risk to the fetus.

Breast Feeding

There are no adequate studies in women for determining infant risk when using this medication during breastfeeding. Weigh the potential benefits against the potential risks before taking this medication while breastfeeding.

Interactions with Medicines

Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are taking clozapine, it is especially important that your healthcare professional know if you are taking any of the medicines listed below. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.

Using clozapine with any of the following medicines is not recommended. Your doctor may decide not to treat you with this medication or change some of the other medicines you take.

• Cisapride


• Dronedarone


• Droperidol


• Fluconazole


• Mesoridazine


• Metoclopramide


• Pimozide


• Posaconazole


• Sparfloxacin

Using clozapine with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.

• Alfuzosin


• Amiodarone


• Amitriptyline


• Amoxapine


• Apomorphine


• Arsenic Trioxide


• Asenapine


• Astemizole


• Azithromycin


• Buspirone


• Carbamazepine


• Chloroquine


• Chlorpromazine


• Cinacalcet


• Clarithromycin


• Clomipramine


• Crizotinib


• Dasatinib


• Delavirdine


• Desipramine


• Diltiazem


• Disopyramide


• Dofetilide


• Dolasetron


• Doxorubicin


• Droperidol


• Duloxetine


• Gatifloxacin


• Gemifloxacin


• Granisetron


• Halofantrine


• Haloperidol


• Hydromorphone


• Ibutilide


• Iloperidone


• Imatinib


• Imipramine


• Indinavir


• Itraconazole


• Ketoconazole


• Lapatinib


• Levofloxacin


• Lithium


• Lumefantrine


• Mate


• Mefloquine


• Methadone


• Mifepristone


• Milnacipran


• Moxifloxacin


• Nelfinavir


• Nilotinib


• Nortriptyline


• Octreotide


• Ofloxacin


• Ondansetron


• Paliperidone


• Pazopanib


• Perflutren Lipid Microsphere


• Procainamide


• Prochlorperazine


• Promethazine


• Protriptyline


• Quetiapine


• Quinine


• Ranolazine


• Salmeterol


• Saquinavir


• Sodium Phosphate


• Sodium Phosphate, Dibasic


• Sodium Phosphate, Monobasic


• Solifenacin


• Sorafenib


• Sotalol


• St John's Wort


• Sunitinib


• Telaprevir


• Telavancin


• Telithromycin


• Terbinafine


• Terfenadine


• Toremifene


• Tramadol


• Trazodone


• Trifluoperazine


• Trimipramine


• Vandetanib


• Vardenafil


• Vemurafenib


• Verapamil


• Voriconazole


• Ziprasidone


• Zotepine

Using clozapine with any of the following medicines may cause an increased risk of certain side effects, but using both drugs may be the best treatment for you. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.

• Aprindine


• Cimetidine


• Ciprofloxacin


• Citalopram


• Encainide


• Erythromycin


• Flecainide


• Fluoxetine


• Fluvoxamine


• Lorcainide


• Nefazodone


• Nicotine


• Paroxetine


• Perphenazine


• Phenobarbital


• Phenytoin


• Propafenone


• Quinidine


• Rifampin


• Ritonavir


• Sertraline


• Thioridazine


• Venlafaxine

Interactions with Food/Tobacco/Alcohol

Certain medicines should not be used at or around the time of eating food or eating certain types of food since interactions may occur. Using alcohol or tobacco with certain medicines may also cause interactions to occur. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.

Using clozapine with any of the following is usually not recommended, but may be unavoidable in some cases. If used together, your doctor may change the dose or how often you use clozapine, or give you special instructions about the use of food, alcohol, or tobacco.

• Grapefruit Juice

Using clozapine with any of the following may cause an increased risk of certain side effects but may be unavoidable in some cases. If used together, your doctor may change the dose or how often you use clozapine, or give you special instructions about the use of food, alcohol, or tobacco.

• Caffeine

Other Medical Problems

The presence of other medical problems may affect the use of clozapine. Make sure you tell your doctor if you have any other medical problems, especially:

• Blood diseases (e.g., agranulocytosis, granulocytopenia), history of or


• Bone marrow disorder or


• Central nervous system depression (not fully awake), severe or


• Intestinal blockage (e.g., paralytic ileus) or


• Seizures (epilepsy), uncontrolled—Should not be used in patients with these conditions.

• Blood vessel problems (poor circulation) or


• Heart attack, recent or history of or


• Heart disease or


• Heart failure or


• Heart rhythm problems (e.g., arrhythmia, long QT syndrome), or history of or


• Hypokalemia (low potassium in the blood) or


• Hypomagnesemia (low magnesium in the blood) or


• Hypotension (low blood pressure) or


• Lung problems or


• Stroke, history of—May cause side effects to become worse.

• Bowel problems (e.g., constipation) or


• Diabetes or


• Difficult urination or


• Enlarged prostate or


• Glaucoma, narrow angle or


• Hyperglycemia (high blood sugar) or


• Liver disease (e.g., hepatitis) or


• Neuroleptic malignant syndrome, history of or


• Seizures, history of—Use with caution. May make these conditions worse.

• Kidney disease or


• Liver disease—Higher blood levels of clozapine may occur, increasing the chance that unwanted effects will occur.

• Phenylketonuria (PKU)—The orally disintegrating tablet contains phenylalanine, which can make this condition worse.

Proper Use of clozapine

Take clozapine exactly as directed. Do not take more of it and do not take it more often than your doctor ordered. Do not miss any doses.

clozapine has been prescribed for your current medical condition only. It must not be given to other people or used for other conditions. Talk to your doctor if you have questions.

Take the tablets with or without food.

If you are using the disintegrating tablet, make sure your hands are dry before you handle the tablet. Do not open the blister pack that contains the tablet until you are ready to take it. Remove the tablet from the blister pack by peeling back the foil, then taking the tablet out. Do not push the tablet through the foil. Place the tablet in your mouth. It should melt quickly. After the tablet has melted, swallow or chew it as desired.

Drink plenty of fluids while taking clozapine to help avoid constipation.

Dosing

The dose of clozapine will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of clozapine. If your dose is different, do not change it unless your doctor tells you to do so.

The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.

• For oral dosage forms (disintegrating tablets or tablets):
  
  • For schizophrenia:
    
    • Adults—At first, 12.5 milligrams (mg) once or two times a day. Your doctor may increase your dose as needed and tolerated. However, the dose is usually not more than 900 mg per day.
    
    
    • Children—Use and dose must be determined by your doctor.
    
    
  
  
  • For prevention of risk of suicidal behavior from occurring again in patients with schizophrenia or schizoaffective disorder:
    
    • Adults—At first, 12.5 milligrams (mg) once or two times a day. Your doctor may increase your dose as needed and tolerated. However, the dose is usually not more than 900 mg per day.
    
    
    • Children—Use and dose must be determined by your doctor.
    
    
  
  

Missed Dose

If you miss a dose of clozapine, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not double doses.

If you miss 2 or more days of clozapine doses, talk to your doctor before you start taking it again. You may need to restart clozapine at a lower dose than you were taking before.

Storage

Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep from freezing.

Keep out of the reach of children.

Do not keep outdated medicine or medicine no longer needed.

Ask your healthcare professional how you should dispose of any medicine you do not use.

Precautions While Using clozapine

It is important that you have your blood tests done when they are scheduled, and that your doctor check your progress at regular visits. Clozapine can cause some very serious blood problems that you may not be able to feel or see. The pharmacy will give you clozapine only if your blood tests show that it is safe for you to take clozapine. Also, your doctor will make sure the medicine is working properly and change the dosage if needed.

If you have been using clozapine regularly, do not stop taking it without first checking with your doctor. Your doctor may want you to gradually reduce the amount you are taking before stopping it completely. This is to help prevent the illness from suddenly returning and to decrease the chance of having symptoms such as headache, nausea, vomiting or diarrhea.

clozapine will add to the effects of alcohol and other central nervous system (CNS) depressants, which are medicines that slow down the nervous system and possibly cause drowsiness. Some examples of CNS depressants are antihistamines or medicine for hay fever, other allergies, or colds; sedatives, tranquilizers, or sleeping medicine; prescription pain medicine or narcotics; medicine for seizures or barbiturates; muscle relaxants; or anesthetics, including some dental anesthetics. Check with your doctor before taking any of the above while you are using clozapine.

Clozapine can temporarily lower the number of white blood cells in your blood, which increases the chance of getting an infection. Let your doctor know right away if you think you have the flu or an infection. Possible signs and symptoms include fever, feeling tired, sore throat, or weakness. Certain precautions you can take when your blood count is low to reduce the risk of infection include:

• If you can, avoid people with infections. Check with your doctor immediately if you think you are getting an infection or if you get a fever or chills, cough or hoarseness, lower back or side pain, or painful or difficult urination.


• Be careful when using a regular toothbrush, dental floss, or toothpick. Your medical doctor, dentist, or nurse may recommend other ways to clean your teeth and gums. Check with your medical doctor before having any dental work done.


• Do not touch your eyes or the inside of your nose unless you have just washed your hands and have not touched anything else in the meantime.

Stop using clozapine and contact your doctor as soon as possible if you have chest pain or discomfort, a fast heartbeat, trouble breathing, or fever and chills. These can be symptoms of a very serious problem with your heart.

Clozapine may cause drowsiness, blurred vision or convulsions (seizures). Do not drive, climb, swim, operate machines, or do anything else that could be dangerous while you are taking clozapine.

clozapine can cause changes in heart rhythms, such as a condition called QT prolongation. It may change the way your heart beats and cause fainting or serious side effects in some patients. Contact your doctor right away if you have any symptoms of heart rhythm problems, such as fast, pounding, or uneven heartbeats.

Dizziness, lightheadedness, or fainting may occur, especially when you get up from a lying or sitting position suddenly. These symptoms are more likely to occur when you begin taking clozapine, or when the dose is increased. Getting up slowly may help. If this problem continues or gets worse, check with your doctor.

clozapine may increase the amount of sugar in your blood. Check with your doctor right away if you have increased thirst or urination. Diabetic patients should check their blood and urine sugar levels more often while taking clozapine. The dose of diabetic medicines may need to be changed.

In some patients, clozapine may cause increased watering of the mouth. Other patients, however, may get dryness of the mouth. For temporary relief of mouth dryness, use sugarless gum or candy, melt bits of ice in your mouth, or use a saliva substitute. However, if your mouth continues to feel dry for more than 2 weeks, check with your medical doctor or dentist. Continuing dryness of the mouth may increase the chance of dental disease, including tooth decay, gum disease, and fungus infections.

Check with your doctor right away if you are having convulsions (seizures); difficulty with breathing; fast heartbeat; high fever; high or low blood pressure; increased sweating; loss of bladder control; severe muscle stiffness; unusually pale skin; or tiredness. These could be symptoms of a serious condition called neuroleptic malignant syndrome (NMS).

clozapine may cause tardive dyskinesia (a movement disorder) among the elderly, especially elderly women. Stop using clozapine and check with your doctor right away if you have any of the following symptoms while taking clozapine: lip smacking or puckering, puffing of the cheeks, rapid or worm-like movements of the tongue, uncontrolled chewing movements, or uncontrolled movements of the arms and legs.

Stop using clozapine and check with your doctor right away if you have pain or tenderness in the upper stomach; pale stools; dark urine; loss of appetite; nausea; unusual tiredness or weakness; or yellow eyes or skin. These could be symptoms of a serious liver problem.

Make sure any doctor or dentist who treats you knows that you are using clozapine. You may need to stop using clozapine several days before having surgery or medical tests.

Do not take other medicines unless they have been discussed with your doctor. This includes prescription or nonprescription (over-the-counter [OTC]) medicines and herbal or vitamin supplements.

clozapine Side Effects

Along with its needed effects, a medicine may cause some unwanted effects. Some side effects may not have signs or symptoms that you can see or feel. Clozapine can cause some very serious blood problems. Your doctor will watch for these by doing blood tests every week or two for as long as you are taking clozapine and for 4 weeks after you stop taking it. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur:

More common

• Blurred vision


• confusion


• dizziness, faintness, or lightheadedness when getting up suddenly from a lying or sitting position


• fainting


• fast, pounding, or irregular heartbeat or pulse


• fever


• low blood pressure


• shakiness in the legs, arms, hands, or feet


• sleepiness or unusual drowsiness


• sweating


• trembling or shaking of the hands or feet


• unusual tiredness or weakness

Less common

• Anxiety


• black, tarry stools


• chest pain


• chills


• convulsions


• cough or hoarseness


• decrease in frequency of urination


• decrease in urine volume


• difficult or labored breathing


• difficulty in passing urine (dribbling)


• discouragement


• dry mouth


• fear or nervousness


• feeling sad or empty


• fever with or without chills


• frequent strong or increased urge to urinate


• general feeling of tiredness or weakness


• headache


• hyperventilation


• irritability


• lack of appetite


• loss of bladder control


• loss of interest or pleasure


• lower back or side pain


• mood or mental changes


• muscle spasm or jerking of all extremities


• painful or difficult urination


• pounding in the ears


• restlessness or need to keep moving


• severe or continuing headache


• shakiness and unsteady walk


• shortness of breath


• slurred speech


• sore throat


• sores, ulcers, or white spots on the lips or in the mouth


• sudden jerky movements of the body


• sudden loss of consciousness


• swollen glands


• throat discomfort


• tightness in the chest


• trouble concentrating


• trouble sleeping


• unsteadiness, trembling, or other problems with muscle control or coordination


• wheezing

Rare

• Absence of or decrease in movement


• dark urine


• decreased appetite


• decreased sexual ability


• difficult or fast breathing or sudden shortness of breath


• increased appetite


• increased sweating


• increased thirst


• increased urination


• lip smacking or puckering


• loss of bladder control


• mental depression


• muscle stiffness (severe)


• nausea


• puffing of the cheeks


• rapid or worm-like movements of the tongue


• swelling or pain in the leg


• trouble breathing


• trouble in urinating


• uncontrolled chewing movements


• uncontrolled movements of the arms and legs


• unusual bleeding or bruising


• unusually pale skin


• vomiting


• weakness


• yellow eyes or skin

Incidence not known

• Abdominal or stomach pain


• bloating


• burning, crawling, itching, numbness, prickling, "pins and needles", or tingling feelings


• clay-colored stools


• confusion as to time, place, or person


• constipation


• darkened urine


• diarrhea


• epileptic seizure that will not stop


• feeling that others are watching you or controlling your behavior


• feeling that others can hear your thoughts


• feeling, seeing, or hearing things that are not there


• holding false beliefs that cannot be changed by fact


• inability to move the eyes


• increased blinking or spasms of the eyelid


• indigestion


• itching


• joint pain


• light-colored stools


• muscle twitching


• pains in the stomach, side, or abdomen, possibly radiating to the back


• rhythmic movement of the muscles


• severe mood or mental changes


• skin rash


• sticking out of the tongue


• swelling around the eyes


• swelling of the body or feet and ankles


• trouble in breathing, speaking, or swallowing


• uncontrolled twisting movements of the neck, trunk, arms, or legs


• unpleasant breath odor


• unusual behavior


• unusual excitement, nervousness, or restlessness


• unusual facial expressions


• unusual weight gain


• upper right abdominal or stomach pain


• vomiting of blood


• yellow eyes or skin

Get emergency help immediately if any of the following symptoms of overdose occur:

Symptoms of overdose

• Change in consciousness


• drowsiness


• increased watering of mouth (severe)


• irregular, fast or slow, or shallow breathing


• loss of consciousness


• pale or blue lips, fingernails, or skin


• pounding or rapid pulse

Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

More common

• Acid or sour stomach


• belching


• feeling of constant movement of self or surroundings


• heartburn


• relaxed and calm sensation of spinning


• sleepiness


• sleeplessness


• unable to sleep

Less common

• Blurred or loss of vision


• change or problem with discharge of semen


• disturbed color perception


• double vision


• halos around lights


• inability to sit still


• increase in body movements


• muscle pain or ache


• muscle weakness


• night blindness


• nightmares


• overbright appearance of lights


• pain in the back, neck, or legs


• pain in the chest below the breastbone


• severe muscle stiffness


• sore tongue


• stuffy nose


• tunnel vision


• unusual drowsiness, dullness, tiredness, weakness, or feeling of sluggishness

Incidence not known

• Blistering, peeling, or loosening of the skin


• difficulty with swallowing


• hives


• increased sensitivity of the skin to sunlight


• painful or prolonged erection of the penis


• red skin lesions, often with a purple center


• red, irritated eyes


• reddening of the skin, especially around the ears


• severe stomach pain


• severe sunburn


• sores, welting, or blisters


• swelling of the eyes, face, or inside of the nose


• swelling of the salivary glands

Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.

Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.

See also: clozapine side effects (in more detail)

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More clozapine resources

• Clozapine Side Effects (in more detail)
• Clozapine Use in Pregnancy & Breastfeeding
• Drug Images
• Clozapine Drug Interactions
• Clozapine Support Group
• 6 Reviews for Clozapine - Add your own review/rating

• Clozapine Prescribing Information (FDA)


• Clozapine Professional Patient Advice (Wolters Kluwer)


• Clozapine Monograph (AHFS DI)


• Clozapine MedFacts Consumer Leaflet (Wolters Kluwer)


• Clozaril Prescribing Information (FDA)


• Clozaril Consumer Overview


• FazaClo Orally Disintegrating Tablets MedFacts Consumer Leaflet (Wolters Kluwer)


• FazaClo Prescribing Information (FDA)


• Fazaclo Consumer Overview

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