Olanzapine
Olanzapine is an antipsychotic used for schizophrenia, bipolar disorder (mania or maintenance), and sometimes for treatment-resistant depression in combination with fluoxetine when a specialist prescribes it.
This medicine is part of the Mental health medicines category.
Generic name: olanzapine
Quick answers
Short replies to searches people often run before speaking to a clinician. For the overview of what the medicine is used for, see the short summary under the page title above.
What is it for?
Olanzapine is an antipsychotic used for schizophrenia, bipolar disorder (mania or maintenance), and sometimes for treatment-resistant depression in combination with fluoxetine when a specialist prescr…
How long does it take to work?
Onset varies by condition and dose. Your GP or pharmacist can explain what to expect and when to review.
What are common side effects?
Common effects include weight gain, increased appetite, sleepiness, dry mouth, constipation, and ankle swelling.
Can you take paracetamol or ibuprofen with it?
Ask your GP or pharmacist before taking Olanzapine with paracetamol or ibuprofen. Many adults use paracetamol for short periods when appropriate; NSAIDs such as ibuprofen need extra checks with your other medicines and health conditions.
More about what Olanzapine is used for
Olanzapine is an antipsychotic used for schizophrenia, bipolar disorder (mania or maintenance), and sometimes for treatment-resistant depression in combination with Fluoxetine when a specialist prescribes it.
Long-acting injections exist for some people who prefer depot treatment — administered by healthcare staff.
How does Olanzapine work, and how long does it take to work?
It affects dopamine and serotonin receptors (and others), which helps control psychotic symptoms and stabilise mood in the conditions for which it is licensed.
It is not a simple “calming” tablet for everyday stress.
How and when should you take Olanzapine?
Tablets are usually taken once daily, often in the evening at first because of sedation. Orally disintegrating tablets are placed on the tongue as directed.
Follow your prescriber’s plan for dose changes; do not stop abruptly.
What are the common side effects of Olanzapine?
Common effects include weight gain, increased appetite, sleepiness, dry mouth, constipation, and ankle swelling. Metabolic changes (glucose, lipids) can occur.
Movement side effects such as tremor or stiffness are possible — report them.
Serious side effects of Olanzapine — when to get urgent help
Seek urgent help for fever, muscle rigidity, confusion, severe allergic reaction, suicidal thoughts, or blood clot symptoms.
Very high blood sugar or diabetic ketoacidosis has been reported rarely — know thirst, frequent urination, and nausea as warning signs.
What if you miss a dose of Olanzapine?
Take when remembered unless nearly time for next dose. Do not double up. For depot injections, attend appointments on schedule.
Who should not take Olanzapine?
Individual assessment for dementia-related illness, narrow-angle glaucoma risk, diabetes control, and heart disease. Pregnancy and breastfeeding need specialist advice.
Can you take paracetamol or ibuprofen with Olanzapine? — other interactions
Smoking cessation can raise olanzapine levels. Sedatives and alcohol add drowsiness. Smoking and some medicines affect drug levels — your team may adjust doses.
Olanzapine in pregnancy and breastfeeding
Discuss with your psychiatrist before changing olanzapine in pregnancy or breastfeeding.
Blood tests and monitoring on Olanzapine
Weight, glucose, lipids, blood pressure, and movement examination may be part of care. Attend clinic reviews.
What might your GP prescribe instead of Olanzapine?
Other antipsychotics, mood stabilisers, or different combinations may be tried if olanzapine is not tolerated or effective.
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Frequently asked questions about Olanzapine
People also ask — common Google searches
- What is Olanzapine used for?
- Olanzapine is an antipsychotic used for schizophrenia, bipolar disorder (mania or maintenance), and sometimes for treatment-resistant depression in combination with Fluoxetine when a specialist prescribes it.
- How long does Olanzapine take to work?
- Onset varies by condition and dose. Your GP or pharmacist can explain what to expect and when to review. Always follow your prescriber’s follow-up plan.
- Can you take Olanzapine with paracetamol or ibuprofen?
- Ask your GP or pharmacist before taking Olanzapine with Paracetamol or Ibuprofen. Many adults use paracetamol for short periods when appropriate; NSAIDs such as ibuprofen need extra checks with your other medicines and health conditions.
- What are the side effects of Olanzapine?
- Common effects include weight gain, increased appetite, sleepiness, dry mouth, constipation, and ankle swelling. Metabolic changes (glucose, lipids) can occur. See the sections below for more detail, including serious side effects and when to seek urgent help.
- Olanzapine vs quetiapine — which is better?
- Both are antipsychotics with different side-effect patterns. Your psychiatrist chooses based on diagnosis, past response, and physical health monitoring.
- Can olanzapine cause diabetes?
- It can raise blood sugar and weight in some people. Your team usually monitors glucose and may adjust lifestyle or treatment if problems appear.
Need personalised advice?
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Often used with
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