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Olanzapine long-acting injection


Olanzapine long-acting injection will be given to you by your clinic doctor or nurse every 2-4 weeks.

The injection may cause you to feel sleepy or dizzy for a few hours afterwards.

If you miss an appointment for an injection, make another appointment as soon as possible.

There are a number of side-effects which you could experience from the treatment. If you are concerned about any, you should discuss them with your doctor.

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About olanzapine long-acting injection

Type of medicine

An antipsychotic injection

Used for

Maintenance of symptom control in adults with schizophrenia and other similar mental health problems

Also called

Zypadhera® (olanzapine embonate)

Available as

Long-acting depot injection

Olanzapine belongs to a group of medicines called antipsychotics. You will have been prescribed it to maintain symptom control of schizophrenia.

Schizophrenia is a mental health condition that causes disordered ideas, beliefs and experiences. Symptoms of schizophrenia include hearing, seeing, or sensing things that are not real, having mistaken beliefs, feeling unusually suspicious, and becoming withdrawn. Olanzapine is used to relieve the symptoms of schizophrenia and other similar mental health problems. It works on the balance of chemical substances in your brain.

Long-acting, or 'depot', injections are used once your symptoms have been eased by taking tablets. The injection slowly releases olanzapine into your body and is given either every two weeks, or every four weeks. The main advantage of a depot injection is that you do not have to remember to take tablets every day.

Before having olanzapine long-acting injection

Some medicines are not suitable for people with certain conditions, and sometimes a medicine can only be used if extra care is taken. For these reasons, before you start having olanzapine long-acting injections, it is important that your doctor knows:

  • If you are pregnant or breastfeeding.

  • If you have a heart condition or blood vessel disease.

  • If you have any problems with the way your liver works, or if you have any problems with the way your kidneys work.

  • If you have prostate problems.

  • If you have any problems with your breathing.

  • If you have any of the following: epilepsy, diabetes (diabetes mellitus), depression, Parkinson's disease, raised pressure in your eye (glaucoma) or a condition which causes muscle weakness, called myasthenia gravis.

  • If you have ever had yellowing of your skin or the whites of your eyes (jaundice).

  • If you have a blood or bone marrow disorder.

  • If you are very constipated or think you may have a blockage in your bowel.

  • If you have had an allergic reaction to a medicine.

  • If you are taking or using any other medicines. This includes any medicines you are taking which are available to buy without a prescription, as well as herbal and complementary medicines.

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How olanzapine long-acting injection is given

  • Before you start the treatment, ask to read the manufacturer's printed information leaflet from inside the pack. The leaflet will give you more information about olanzapine, and it will also provide you with a full list of the side-effects which you could experience.

  • Olanzapine long-acting injection will be given to you in an outpatient clinic by a doctor or nurse. The injection is given into a muscle in your bottom (buttocks). As a routine, you will be asked to stay in the clinic where you can be observed for at least three hours after each injection. This is because it can make you feel tired or dizzy after it is given. You will be advised not to drive and not to use tools or machines for the remainder of the day.

  • You may be asked to continue taking your current tablets for a short while after you have had your first injection. This is because it can take a few weeks before you feel the full effect from the injection.

  • Treatment with olanzapine is usually long-term so that your symptoms don't return.

Getting the most from your treatment

  • Your treatment will require careful monitoring to make sure that you get the best possible benefit from olanzapine. Keep your regular doctor's appointments so that you get your injections on time, and your progress can be checked. If you miss an appointment for an injection, contact the hospital to arrange for another appointment as soon as possible.

  • Olanzapine could cause your skin to become more sensitive to sunlight than normal. Avoid strong sunlight and sunbeds, and use a sun cream with a high sun protection factor even on bright but cloudy days.

  • If you drink alcohol, ask your doctor for advice about drinking while you are on olanzapine. Alcohol can increase the chance that you will experience side-effects and may not be advisable for you.

  • If you have diabetes you may need to check your blood sugar (glucose) more frequently, as olanzapine can affect the levels of sugar in your blood. Your doctor will advise you about this.

  • If you are having any dental treatment or an operation, tell the person carrying out the treatment that you have had an olanzapine injection. This is important because it may interfere with the anaesthetic you receive.

  • If you buy or take any 'over-the-counter' medicines, check with a pharmacist that they are suitable for you to take with olanzapine.

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Can olanzapine long-acting injection cause problems?

Along with their useful effects, most medicines can cause unwanted side-effects although not everyone experiences them. The table below contains some of the more common ones associated with olanzapine. The best place to find a full list of the side-effects which can be associated with your medicine, is from the manufacturer's printed information leaflet supplied with the medicine. Alternatively, you can find an example of a manufacturer's information leaflet in the reference section below. Speak with your doctor or pharmacist if any of the following continue or become troublesome.

Very common olanzapine side-effects (these affect more than 1 in 10 people)

What can I do if I experience this?

Feeling sleepy, tired or dizzy

Do not drive and do not use tools or machines while affected

Increased weight

Eat a well-balanced diet. Speak with your doctor if your weight becomes troublesome

Changes to some blood test results

Your doctor will monitor for these

Common olanzapine side-effects

(these affect fewer than 1 in 10 people)

What can I do if I experience this?

Feeling restless

Speak with your doctor about this

Pain at the site of the injection

This should not last long. If the area becomes red, swollen or 'lumpy', let your doctor know

Dry mouth

Try chewing sugar-free gum or sucking sugar-free sweets


Drink plenty of water, and eat a well-balanced diet containing plenty of fruit, vegetables, and fibre

Unusual or uncontrollable muscle movements, shakiness

Speak with your doctor about these

Increased appetite and weight, rash, feeling hot, reduced interest in sex, erectile dysfunction, aches and pains

Discuss these with your doctor if any become troublesome

Important: if you experience symptoms such as muscle stiffness, a very high temperature, feeling confused or sweaty, a fast heartbeat, and urinary incontinence, you should contact your doctor immediately. These can be signs of a rare but serious condition known as neuroleptic malignant syndrome.

If you experience any other symptoms which you think may be due to the injection, speak with your doctor or pharmacist for further advice.

Important information about all medicines

Important information about all medicines

If you suspect that you have had an overdose of this medicine, go to the accident and emergency department of your local hospital at once.

This medicine is for you. Never give it to other people even if their condition appears to be the same as yours.

Do not keep out-of-date or unwanted medicines. Take them to your local pharmacy which will dispose of them for you.

If you have any questions about this medicine ask your pharmacist.

Report side effects to a medicine or vaccine

If you experience side effects, you can report them online through the Yellow Card website.

Further reading and references

Article history

The information on this page is written and peer reviewed by qualified clinicians.

  • Next review due: 11 Dec 2025
  • 12 Dec 2022 | Latest version

    Last updated by

    Michael Stewart, MRPharmS

    Peer reviewed by

    Sid Dajani
  • 20 Aug 2010 | Originally published

    Authored by:

    Helen Allen
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