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Clozapine (Oral route)

Pronunciation:

KLOE-za-peen

Brand Names:

  • Clozaril
  • FazaClo
  • Versacloz

Dosage Forms:

  • Tablet
  • Tablet, Disintegrating
  • Suspension

Warnings:

Oral route(Tablet;Tablet, Disintegrating;Suspension)

Risks associated with the use of clozapine include agranulocytosis, orthostatic hypotension, seizures, myocarditis and cardiomyopathy. Agranulocytosis can lead to serious infection and death. Monitor white blood cell count (WBC) and absolute neutrophil count (ANC) prior to and during treatment. Monitor for symptoms of agranulocytosis and infection. Clozapine is only available through a restricted program that requires prescribers, patients, and pharmacies to enroll because of the risk of agranulocytosis. Orthostatic Hypotension, bradycardia, syncope, cardiac arrest, and seizures have occurred. The risk is dose-related. Initiate treatment at 12.5 mg, titrate gradually, and use divided dosing. Use with caution in patients with history of or risk factors for seizure. Myocarditis and cardiomyopathy have occurred and can be fatal. Discontinue and obtain cardiac evaluation if findings suggest these cardiac reactions. Elderly patients with dementia-related psychosis treated with atypical antipsychotic drugs are at an increased risk of death. Clozapine is not approved for the treatment of patients with dementia-related psychosis .

Classifications:

Therapeutic—

Antipsychotic

Chemical—

Dibenzodiazepine

Uses of This Medicine:

Clozapine is used to treat schizophrenia (mental disorder) in patients who have used other medicines that did not work well. It is also used to prevent suicidal behavior in patients with schizophrenia or schizoaffective disorder. Clozapine changes some of the chemicals in the brain that are thought to cause schizophrenia.

This medicine is only available through a restricted program. You might be asked to read and sign papers that explain how the medicine works and some of the unwanted effects.

Before Using This Medicine:

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 this medicine, the following should be considered:

Allergies—

Tell your doctor if you have ever had any unusual or allergic reaction to this medicine 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.

Children—

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.

Older adults—

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. This medicine should not be used for behavioral problems in older adults with dementia.

Pregnancy—

Pregnancy CategoryExplanation
All TrimestersBAnimal 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.

Other 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 this medicine, 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 this medicine 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.

  • Amifampridine
  • Cisapride
  • Dronedarone
  • Droperidol
  • Fluconazole
  • Mesoridazine
  • Metoclopramide
  • Pimozide
  • Piperaquine
  • Posaconazole
  • Saquinavir
  • Sparfloxacin
  • Terfenadine
  • Thioridazine
  • Ziprasidone

Using this medicine 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.

  • Abiraterone Acetate
  • Alfuzosin
  • Amiodarone
  • Amoxapine
  • Amprenavir
  • Apomorphine
  • Aprepitant
  • Armodafinil
  • Arsenic Trioxide
  • Asenapine
  • Astemizole
  • Atazanavir
  • Azithromycin
  • Balofloxacin
  • Bedaquiline
  • Bepridil
  • Besifloxacin
  • Boceprevir
  • Bosentan
  • Bupropion
  • Buspirone
  • Caffeine
  • Carbamazepine
  • Chloroquine
  • Chlorpromazine
  • Cimetidine
  • Cinacalcet
  • Cinoxacin
  • Ciprofloxacin
  • Citalopram
  • Clarithromycin
  • Clobazam
  • Cobicistat
  • Conivaptan
  • Crizotinib
  • Cyclobenzaprine
  • Dabrafenib
  • Darunavir
  • Dasatinib
  • Deferasirox
  • Dexamethasone
  • Diltiazem
  • Disopyramide
  • Disulfiram
  • Dofetilide
  • Dolasetron
  • Domperidone
  • Doxorubicin
  • Doxorubicin Hydrochloride Liposome
  • Efavirenz
  • Enoxacin
  • Enzalutamide
  • Erythromycin
  • Escitalopram
  • Eslicarbazepine Acetate
  • Ethinyl Estradiol
  • Etravirine
  • Famotidine
  • Fingolimod
  • Flecainide
  • Flumequine
  • Fluoxetine
  • Fluvoxamine
  • Fosamprenavir
  • Fosphenytoin
  • Gatifloxacin
  • Gemifloxacin
  • Granisetron
  • Halofantrine
  • Hydromorphone
  • Hydroquinidine
  • Ibutilide
  • Iloperidone
  • Imatinib
  • Indinavir
  • Itraconazole
  • Ivabradine
  • Ketoconazole
  • Lapatinib
  • Levofloxacin
  • Lithium
  • Lomefloxacin
  • Lomitapide
  • Lopinavir
  • Lumefantrine
  • Mate
  • Mefloquine
  • Methadone
  • Methoxsalen
  • Mexiletine
  • Mibefradil
  • Miconazole
  • Mifepristone
  • Milnacipran
  • Mitotane
  • Mizolastine
  • Modafinil
  • Montelukast
  • Moricizine
  • Moxifloxacin
  • Nadifloxacin
  • Nafcillin
  • Nalidixic Acid
  • Nefazodone
  • Nelfinavir
  • Nevirapine
  • Nilotinib
  • Norfloxacin
  • Octreotide
  • Ofloxacin
  • Omeprazole
  • Oxcarbazepine
  • Oxolinic Acid
  • Paliperidone
  • Pasireotide
  • Pazopanib
  • Pazufloxacin
  • Pefloxacin
  • Pentamidine
  • Perflutren Lipid Microsphere
  • Perphenazine
  • Phenobarbital
  • Phenylpropanolamine
  • Phenytoin
  • Pipemidic Acid
  • Pixantrone
  • Prednisone
  • Procainamide
  • Prochlorperazine
  • Promethazine
  • Propranolol
  • Protriptyline
  • Prulifloxacin
  • Quetiapine
  • Quinidine
  • Quinine
  • Ranolazine
  • Regorafenib
  • Rifabutin
  • Rifampin
  • Rifapentine
  • Rosoxacin
  • Rufinamide
  • Rufloxacin
  • Salmeterol
  • Sertindole
  • Sertraline
  • Sodium Phosphate
  • Sodium Phosphate, Dibasic
  • Sodium Phosphate, Monobasic
  • Solifenacin
  • Sorafenib
  • Sotalol
  • St John's Wort
  • Sunitinib
  • Tacrolimus
  • Tegafur
  • Telaprevir
  • Telavancin
  • Telithromycin
  • Terbinafine
  • Teriflunomide
  • Tetrabenazine
  • Thiabendazole
  • Ticagrelor
  • Ticlopidine
  • Tipranavir
  • Topiramate
  • Toremifene
  • Trazodone
  • Trifluoperazine
  • Trimipramine
  • Vandetanib
  • Vardenafil
  • Vemurafenib
  • Verapamil
  • Vinflunine
  • Voriconazole
  • Zileuton
  • Zotepine

Other interactions—

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 this medicine 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 this medicine, or give you special instructions about the use of food, alcohol, or tobacco.

  • Grapefruit Juice
  • Tobacco

Using this medicine 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 this medicine, 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 this medicine. Make sure you tell your doctor if you have any other medical problems, especially:

  • Alcohol abuse, history of or
  • Blood clotting problems (eg, deep vein thrombosis, pulmonary embolism) or
  • Blood vessel problems (poor circulation) or
  • Head injury, history of or
  • Heart attack, recent or history of or
  • Heart disease or
  • Heart failure or
  • Heart rhythm problems (eg, arrhythmia, long QT syndrome, slow heart rate), 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.
  • Blood diseases (eg, agranulocytosis, granulocytopenia), history of or
  • Bone marrow disorder or
  • Intestinal blockage (eg, paralytic ileus) or
  • Seizures (epilepsy), poorly controlled—Should not be used in patients with these conditions.
  • Bowel problems (eg, constipation) or
  • Diabetes or
  • Difficult urination or
  • Dyslipidemia (high fat in the blood) or
  • Enlarged prostate or
  • Glaucoma, narrow angle or
  • Hyperglycemia (high blood sugar) or
  • Liver disease (eg, hepatitis) or
  • Neuroleptic malignant syndrome, history of or
  • Seizures, history of—Use with caution. May make these conditions worse.
  • Kidney disease or
  • Liver disease—Use with caution. The effects may be increased because of slower removal of the medicine from the body.
  • Phenylketonuria (PKU)—The orally disintegrating tablet contains phenylalanine, which can make this condition worse.

Proper Use of This Medicine:

Take this medicine only as directed by your doctor. Do not use more of it, do not use it more often, and do not use it for a longer time than your doctor ordered. Do not miss any doses.

This medicine comes with a patient information insert. Read and follow the instructions carefully. Ask your doctor if you have any questions.

Take the oral liquid or tablet 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.

Shake the bottle of the oral liquid for 10 seconds before each use. Measure the dose with the dosing syringe that comes with the package. Wash the oral syringe with warm water after using it.

Drink plenty of fluids with this medicine to help prevent constipation.

Dosing—

The dose of this medicine 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 this medicine. 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, suspension, or tablets):
    • For schizophrenia or prevention of suicidal behavior:
      • Adults—At first, 12.5 milligrams (mg) per day as a single dose or 2 times per day. Your doctor may adjust your dose as needed. 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 this medicine, 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 might have to restart the medicine at a lower dose than you were taking before.

Storage—

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.

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

Do not refrigerate or freeze the oral liquid. Throw away any unused medicine 100 days after opening the bottle for the first time.

Precautions While Using This Medicine:

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

If you have been using this medicine 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.

This medicine 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 this medicine.

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.

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, operate machines, or do anything else that could be dangerous while you are taking this medicine.

This medicine can cause changes in your heart rhythm, such as a condition called QT prolongation. It may 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 this medicine, or when the dose is increased. Getting up slowly may help. If this problem continues or gets worse, check with your doctor.

This medicine 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 than normal while taking this medicine.

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).

This medicine may cause tardive dyskinesia (a movement disorder) among the elderly, especially elderly women. Stop using this medicine and check with your doctor right away if you have any of the following symptoms while taking this medicine: 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.

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 this medicine. You may need to stop using this medicine 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 (eg, St. John's wort) or vitamin supplements.

Side Effects of This Medicine:

Along with its needed effects, a medicine may cause some unwanted effects. 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
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 the frequency of urination
decrease in urine volume
difficult or labored breathing
difficulty in passing urine (dribbling)
discouragement
dry mouth
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
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
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
Rare
Absence of or decrease in movement
change in appetite
dark urine
decreased sexual ability
difficult or fast breathing or sudden shortness of breath
increased sweating
increased thirst
increased urination
lip smacking or puckering
muscle stiffness (severe)
nausea
puffing of the cheeks
rapid or worm-like movements of the tongue
swelling or pain in the leg
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
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 with speaking
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

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
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
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.


Last Updated: 4/4/2014

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