Clozapine is a drug to relieve symptoms of schizophrenia, which is a mental disorder that causes a person to experience hallucinations, delusions, and impaired thinking and behavior. This drug can also be used to treat symptoms of psychosis in patients with Parkinson's syndrome.  

Clozapine is an antipsychotic that balances natural brain chemicals (neurotransmitters) by blocking several receptors, including dopamine, histamine, and serotonin receptors in the brain. With more balanced levels of neurotransmitters, complaints or symptoms will subside.

Clozapine trademarks: Clorilex, Clozapine, Clozaril, Clozer, Cycozam, Lozap, Nuzip, Sizoril

What is Clozapine

class Antipsychotic
Category Prescription drugs
Benefit Reducing symptoms in schizophrenia , as well as treating psychosis in people with Parkinson's disease
Consumed by Mature
Clozapine for pregnant and lactating women Category B: Animal studies have not demonstrated a risk to the fetus, but there are no controlled studies in pregnant women. Clozapine may be absorbed into breast milk. If you are breastfeeding, do not use this medicine before consulting a doctor.
Form Tablet

Precautions Before Taking Clozapine

Clozapine should only be used as prescribed by a doctor. Below are some things to consider before taking clozapine:

  • Do not take clozapine if you are allergic to this drug. Always tell your doctor about any allergies you have.
  • Tell your doctor if you have or currently have hypertension, blood disorders , head injury, seizures , liver disease, electrolyte disturbances , kidney disease, glaucoma , high cholesterol, pheochromocytoma , enlarged prostate, diabetes , constipation, or heart disease , including heart attack and arrhythmia .
  • Do not drive a vehicle or do activities that require alertness after taking clozapine, as this medicine can cause dizziness, sudden loss of consciousness or fainting , and seizures.
  • Tell your doctor if you have dementia. Clozapine should not be used for psychotic conditions associated with dementia .
  • Tell your doctor if you are taking any medications, supplements or herbal products.
  • Tell your doctor if you are pregnant, breastfeeding or planning a pregnancy.
  • Follow the examination schedule given by the doctor while undergoing treatment with clozapine. This is so the doctor can monitor your condition and the success of therapy.
  • Do not smoke while taking clozapine, as this may decrease the effectiveness of this drug.
  • See your doctor immediately if you have an allergic drug reaction , serious side effects, or overdose after taking clozapine.

Dosage and Instructions for Use of Clozapine

Your doctor will give you clozapine according to your age and the condition you want to treat. The following are general doses of clozapine by age and intended use:

Goal: Reduce symptoms in people with schizophrenia

  • Adult: Initially 12.5 mg, 1–2 times daily. The dose may be increased by 25–50 mg per day, according to patient response, to a target dose of 300–450 mg per day at the end of the 2nd week.
  • Elderly: Initial dose is 12.5–25 mg per day. The increase in the dose given will be adjusted according to the patient's response to the drug.

Purpose: To treat psychosis in patients with Parkinson's disease

  • Adults: The initial dose of 12.5 mg is taken at bedtime at night. Within a week, the dose can be increased to a general dose of 25–37.5 mg per day. The maximum dose is 100 mg per day.

How to Take Clozapine Correctly

Follow the doctor 's advice and read the instructions on the medicine package when you are going to take clozapine. Do not increase or decrease the dose of the drug without consulting your doctor first.

This medicine can be taken before or after meals. Try to take clozapine at the same time every day for maximum treatment results.

For patients who forget to take clozapine, it is recommended to consume it immediately if the gap with the next consumption schedule is not too close. If it is close, ignore it and do not double the next dose.

Do not stop taking clozapine suddenly because it can make the condition worse. The doctor will reduce the dose gradually if the use of the drug needs to be stopped.

Store clozapine in a cool, dry place. Keep the medicine out of direct sunlight and the reach of children.

Clozapine Interactions with Other Drugs

Listed below are some of the side effects of drug interactions that can occur if clozapine is used with other medicines:

  • Increased risk of central nervous system depression when used with antihistamines, benzodiazepines or opioids
  • Increased risk of heart rhythm disturbances when used with ondansetron , oxytocin, papaverine , pimozide, or sertraline
  • Increased risk of developing blood disorders when used with  phenylbutazone , primaquine , sulfamethizole , or  procainamide
  • Decreased effect of norepinephrine therapy
  • Increased levels and effects of clozapine when used with ciprofloxacin , enoxacin, fluvoxamine , caffeine, or birth control pills
  • Increased risk of seizures when used with valproic acid
  • Increased risk of developing neuroleptic malignant syndrome when used with lithium
  • Increased risk of developing tardive dyskinesia when used with trihexyphenidyl

Clozapine Side Effects and Dangers

Side effects that can occur after taking clozapine include:

  • Dizziness, difficulty keeping balance, or dizziness
  • Drowsiness
  • Dry mouth or it's watery
  • Nervous
  • Headache
  • Shaking ( tremors )
  • Blurred vision
  • Constipation
  • Weight gain

Check with your doctor if the side effects above don't go away or get worse. Immediately see a doctor if you experience an allergic drug reaction or more serious side effects, such as:

  • Symptoms of neuroleptic malignant syndrome , such as fever, muscle stiffness, fatigue, confusion, irregular heartbeat, and infrequent urination (BAK)
  • Changes in mood or mood
  • Twitching in the face or in the hands that won't stop
  • Tremors or vibrations in the hands that don't get better
  • Seizures, fainting, weakness, or loss of consciousness
  • Stomach pain, loss of appetite, jaundice , or severe nausea and vomiting
  • Uncontrolled body movements
  • Stopping breathing during sleep ( sleep apnea )
  • Difficult BAK or just can't hold BAK
  • Easy bruising , nosebleeds, or other abnormal bleeding
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