Generic Clozaril

Common use

Clozaril is an atypical antipsycotic. It is used to treat schizophrenia in patients who do not respond to other medicines. It decrease the risk of suicidal behavior. It affects certain chemicals in the brain.



Dosage and directions

Take Clozaril as prescribed by your doctor. Take it with or without food. Take with food to reduce stomach irritation if stomach upset occurs. Continue to take the medicine even if you feel well. Do not stop taking it suddenly without your doctor's advice.



Precautions

Tell your doctor about all your conditions, especially if you are pregnant or plan to become pregnant, breastfeeding, if you have any allergies, if you have a history of blood clots, blood problems, high blood cholesterol levels, heart problems, or lung or breathing problems, if you have a history of an enlarged prostate; prolonged, painful erections; liver or kidney problems; seizures (eg, epilepsy); glaucoma; stomach or bowel problems; or dementia, if you have poor health, diabetes, or a family member with diabetes, or you are very overweight, if you have decreased activity of enzymes that metabolize certain medicines.



Contraindications

You should not to take Clozaril if you have allergy to it, you have severe drowsiness, you have uncontrolled seizures (epilepsy) or loss of bowel muscle movement (paralytic ileus), you have bone marrow problems, other blood cell problems, or a history of blood problems caused by Clozaril, you are taking other medicines that may cause blood problems.



Possible side effects

The most common side effects are dry mouth, headache, dizziness, heartburn, increased sweating or saliva production, lightheadedness when you stand up; nausea; strange dreams; trouble sleeping; weight gain.

Severe side effects include: severe allergic reactions (rash; hives; difficulty breathing; tightness in the chest; swelling of the mouth, face, lips, or tongue); agitation; calf pain or tenderness; chest pain; confusion; dark urine; decreased coordination; fainting; fast or irregular heartbeat; fever, chills, or sore throat; increased hunger, thirst, or urination; infection; involuntary movements of the tongue, face, mouth, or jaw (tongue sticking out, puffing of cheeks, mouth puckering, chewing movements); loss of appetite; numbness of an arm or leg; rapid breathing; restlessness; seizures; severe headache, dizziness, or vomiting; severe or persistent nausea or constipation; severe stomach pain; shortness of breath; stiff muscles; sudden, unusual weight gain; swelling of the hands, ankles, or feet; tremor; trouble swallowing; uncontrolled muscle movements; unusual mental or mood changes; unusual tiredness or weakness; vision changes; vomiting; yellowing of the skin or eyes.



Drug interaction

Tell your doctor about all medicines you are taking and especially: benzodiazepines (lorazepam) or other medicines for mental or mood problems because the risk of heart or breathing problems may be increased; cimetidine, erythromycin, quinolone antibiotics (ciprofloxacin), risperidone, or selective serotonin reuptake inhibitors (SSRIs) (eg, fluoxetine) because they may increase the risk of Clozaril's side effects; barbiturates (phenobarbital), hydantoins (phenytoin), nicotine, or rifampin because they may decrease Clozaril's effectiveness ; antiarrhythmics (eg, propafenone, quinidine), anticholinergics (benztropine), carbamazepine, debrisoquin, dextromethorphan, medicines for depression or high blood pressure, phenothiazines (chlorpromazine), or tricyclic antidepressants (amitriptyline) because the risk of their side effects may be increased by Clozaril.



Missed dose

If you miss a dose of Clozaril, take it as soon as possible. If it is almost time for your next dose, skip the missed dose. Go back to your regular dosing schedule. Do not take 2 doses at once. If you miss taking a dose of Clozaril for more than 2 days do not start taking it again. Contact your doctor right away for instructions.



Overdose

Symptoms of overdose are drowsiness, slow or difficult breathing, dizziness, excessive salvation, fainting, coma, fast ot irregular heartbeats. If you suspect overdose seek medical attention immediately.



Storage

Store Clozaril at room temperature, between 59 and 86 degrees F (15 and 30 degrees C). Store away from heat, moisture, and light. Do not store in the bathroom. Keep Clozaril out of the reach of children and away from pets.



Disclaimer

We provide only general information about medications which does not cover all directions, possible drug integrations, or precautions. Information at the site cannot be used for self-treatment and self-diagnosis. Any specific instructions for a particular patient should be agreed with your health care adviser or doctor in charge of the case. We disclaim reliability of this information and mistakes it could contain. We are not responsible for any direct, indirect, special or other indirect damage as a result of any use of the information on this site and also for consequences of self-treatment.

Clinical Verification

Last Clinically Updated: August 15, 2026

Written By

Dr. Elena Vance, PharmD

Clinical Specialist in Neuropharmacology

Fact Checked By

Marcus Thorne, MS

Biomedical Data & FDA Label Verification

Medically Reviewed By

Dr. Arthur Campbell, MD

Board-Certified Psychiatrist (ABPN)