ONZAPIN

Onzapin 15 mg and 20 mg contains the active substance olanzapine. It is an antipsychotic medicine used in adults for schizophrenia, moderate to severe manic episodes and the prevention of recurrence in bipolar disorder in patients who previously responded to olanzapine.

Onzapin is supplied as an orodispersible tablet that dissolves in the mouth. It must be taken every day according to the precise treatment plan prescribed by a psychiatrist.

Onzapin – what is it used for and how should it be taken?

What is Onzapin used for?

• Schizophrenia, including symptoms such as hallucinations, false beliefs, unusual suspiciousness, agitation and social withdrawal.
• Moderate to severe manic episodes, which may involve excessive energy, an abnormally elevated mood, rapid speech, a reduced need for sleep and marked agitation.
• Prevention of recurrence in bipolar disorder in patients whose manic episode previously responded to olanzapine.

Onzapin is not an occasional calming or sleeping medicine and should not be used for everyday stress, temporary nervousness or insomnia without psychiatric assessment.

How should Onzapin be taken?

It is generally taken once daily. The total daily dose of olanzapine may range from 5 mg to 20 mg, but the precise strength and dose must be determined by the doctor.

The official product information states that the usual initial dose depends on the indication:

• 10 mg daily for schizophrenia;
• 15 mg daily as monotherapy for a manic episode or 10 mg daily when used in combination treatment;
• 10 mg daily for the prevention of recurrence in bipolar disorder.

This information is not a self-dosing guide. The 15 mg and 20 mg tablets are higher-strength preparations and should be used only when specifically prescribed.

• Take the medicine at approximately the same time every day.
• It may be taken with or without food.
• Handle the tablet with dry hands because it breaks easily.
• Place it on the tongue, allow it to dissolve and then swallow.
• It may also be dispersed in water, orange juice, apple juice, milk or coffee and taken immediately.
• Do not independently change, skip or increase the dose.

If a dose is missed: take it when remembered unless it is almost time for the next dose. Do not take two doses on the same day.

When should Onzapin not be taken?

• if you are allergic to olanzapine or any of the other ingredients;
• if you have been diagnosed with certain forms of glaucoma, particularly a risk of angle-closure glaucoma.

Onzapin is not indicated for children or adolescents under 18 years of age.

Weight, blood-glucose and lipid monitoring

Olanzapine may cause a significant increase in appetite and body weight and may increase blood glucose, cholesterol and triglycerides.

The doctor may monitor body weight, waist circumference, blood glucose, lipid levels, blood pressure and liver function before and during treatment.

Pronounced thirst, frequent urination, unusual hunger, weakness or rapid changes in body weight should be reported to the doctor.

Special warnings and precautions

Tell the doctor if you have diabetes, high cholesterol or triglycerides, liver or kidney disease, heart disease, low blood pressure, epilepsy, Parkinson’s disease, an enlarged prostate, difficulty urinating, an intestinal disorder, a blood disorder, a previous stroke or a personal or family history of blood clots.

Olanzapine is not recommended in older people with dementia-related psychosis because of an increased risk of stroke, serious adverse effects and death. It may worsen symptoms in patients with Parkinson’s disease.

Abnormal movements and neuroleptic malignant syndrome

Report involuntary or unusual movements, particularly of the face, mouth or tongue.

High temperature, severe muscle stiffness, rapid breathing, sweating and altered consciousness may indicate neuroleptic malignant syndrome and require emergency treatment.

Interactions

Tell the doctor about all medicines and supplements, particularly antidepressants, anxiety and sleep medicines, other antipsychotics, sedatives, Parkinson’s medicines, carbamazepine, fluvoxamine, ciprofloxacin and medicines that lower blood pressure.

Avoid alcohol because it may markedly increase drowsiness and impair psychomotor reactions.

Starting or stopping smoking may affect olanzapine metabolism. Inform the doctor because monitoring or dose adjustment may be required.

Pregnancy and breastfeeding

During pregnancy, Onzapin should be used only after medical assessment. Do not discontinue treatment independently after learning that you are pregnant.

Newborn babies exposed during the final trimester may experience tremor, muscle stiffness or weakness, drowsiness, agitation, breathing problems or feeding difficulties.

Breastfeeding is not recommended because small amounts of olanzapine pass into breast milk.

Driving

Onzapin may cause drowsiness, dizziness and slowed reactions. Do not drive or operate machinery if affected.

Possible side effects

Very common effects include weight gain, drowsiness and increased prolactin levels.

Common effects may include increased appetite, elevated blood glucose and lipids, dizziness when standing, tremor and other movement disorders, dry mouth, constipation, fatigue, swelling of the hands or feet, rash, joint pain, sexual dysfunction and temporary increases in liver enzymes.

Overdose

An overdose may cause a rapid heartbeat, aggression, agitation, speech problems, abnormal movements, confusion, seizures, impaired consciousness, coma, blood-pressure changes, abnormal heart rhythm and breathing difficulties.

Contact emergency medical services immediately and take the medicine pack with you.

Storage

• Keep out of the sight and reach of children.
• Keep in the original packaging.
• Remove the tablet from the blister immediately before use.
• Do not use after the expiry date.
• Return unused medicine to a pharmacy that collects pharmaceutical waste.

Composition

Each orodispersible tablet contains 15 mg or 20 mg of olanzapine.

The tablets contain aspartame: 8.4 mg in the 15 mg tablet and 11.2 mg in the 20 mg tablet. Aspartame is a source of phenylalanine and may be harmful to people with phenylketonuria.

Other olanzapine medicines:

• Zalasta Q-Tab
• Zalasta

Important: these medicines may differ in strength and pharmaceutical form. Substitution requires confirmation that the prescribed dose and dosage form are equivalent.

Official sources:

• ALIMS – Patient Information Leaflet for Onzapin
• ALIMS – Summary of Product Characteristics for Onzapin

Official product information revised in July 2024. Information prepared on 1 August 2026.