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Asenapine tablets

Sycrest

The usual dose is one tablet (5 mg or 10 mg), taken in the morning and evening. Place the tablet under your tongue and allow it dissolve there. Do not eat or drink for 10 minutes afterwards.

The most common side-effects are drowsiness and anxiety.

Keep your regular appointment with your doctor so your progress can be checked.

Continue reading below

About asenapine tablets

Type of medicine

An antipsychotic medicine

Used for

Episodes of mania associated with bipolar disorder in adults

Also called

Sycrest®

Available as

Sublingual (dissolve under the tongue) tablets

Bipolar disorder is a long-term condition where you have periods of lows (depression) and periods of highs (mania or hypomania).

Asenapine will have been given to you to treat episodes of mania caused by bipolar disorder. It is not known exactly how it works, but it is thought to adjust the levels of certain chemicals in your brain which affect your mood. This decreases the intensity and frequency of the manic episodes you experience.

Before taking asenapine tablets

Some medicines are not suitable for people with certain conditions, and sometimes a medicine may only be used if extra care is taken. For these reasons, before you start taking asenapine, 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 liver, kidney, or prostate problems.

  • If you have breathing problems.

  • If you have any of the following: epilepsy, dementia, Parkinson's disease, depression, raised pressure in your eye (glaucoma), or a condition causing muscle weakness, known as myasthenia gravis.

  • If you have a blood disorder.

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

  • If you have a condition called phaeochromocytoma, a tumour on your adrenal gland.

  • If you have ever had an allergic reaction to any 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 to take asenapine tablets

  • Before you start this treatment, read the manufacturer's printed information leaflet from inside your pack. The manufacturer's leaflet will give you more information about asenapine tablets and a full list of side-effects which you may experience from taking them.

  • Take asenapine tablets exactly as your doctor tells you to. The usual dose is one tablet twice daily, with the doses taken in the morning and the evening. There are two strengths of tablet - 5 mg and 10 mg. You may be started on one strength of the tablet and then switched to the other - this will depend upon how your symptoms respond to the medicine.

  • Peel back the coloured tab covering the blister packaging and remove the tablet (make sure your hands are dry as you do this). Place the tablet under your tongue and allow it to dissolve there - this will only take a few seconds. In order to make sure all the medicine has been absorbed, do not eat or drink anything for 10 minutes afterwards.

  • If you are also taking other medicines at the same times of day as asenapine, take your other medicines first. Asenapine tablets should be taken last.

  • If you forget to take a dose, take it as soon as you remember, unless it is nearly time for your next dose, in which case leave out the missed dose. Do not take two doses together to make up for a forgotten dose.

Getting the most from your treatment

  • Your treatment will require careful monitoring to make sure that you get the best possible benefit from asenapine. Keep your regular doctor's appointments so that your progress can be checked. You may need to have some tests from time to time.

  • Treatment with asenapine is usually long-term unless you experience an adverse effect. Keep taking the tablets until your doctor tells you otherwise. Stopping suddenly can cause problems and your doctor will want you to reduce your dose very gradually if this becomes necessary.

  • Asenapine may cause your skin to become more sensitive to sunlight than normal. Use a sunscreen that protects against UVA light and has a sun protection factor (SPF) of at least 15, especially in strong sunlight or until you know how your skin reacts. Do not use sunbeds.

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

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

  • If you are having any dental treatment or an operation, tell the person carrying out the treatment which medicines you are taking. This is important because asenapine may interfere with any anaesthetic you receive.

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

Continue reading below

Can asenapine 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 most common ones associated with asenapine tablets. You will find a full list in the manufacturer's information leaflet supplied with your medicine. The unwanted effects often improve as your body adjusts to the new medicine, but speak with your doctor or pharmacist if any of the following continue or become troublesome.

Common asenapine side-effects

What can I do if I experience this?

Feeling dizzy, or light-headed, feeling sick (nausea)

This should pass as your body adjusts; in the meantime, try getting up more slowly and sticking to simple foods

Feeling tired, or sleepy

Do not drive and do not use tools or machines if this happens. Do not drink alcohol

Anxiety, increased appetite and weight, unusual movements, shaking, feeling weak, changes in the way things taste or feel in your mouth, producing too much saliva

Discuss these with your doctor if any become troublesome

Important: if you experience any muscle stiffness, with a high temperature, confusion, a fast heartbeat and sweating, contact your doctor immediately. These may be signs of a rare but serious condition known as neuroleptic malignant syndrome.

Important: if you develop any abnormal face or body movements, or feel very restless, speak with your doctor about this as soon as possible.

If you experience any other symptoms which you think may be due to this medicine, speak with your doctor or pharmacist.

How to store asenapine

  • Keep all medicines out of the reach and sight of children.

  • Store in a cool, dry place, away from direct heat and light.

Important information about all medicines

Important information about all medicines

Never take more than the prescribed dose. If you suspect that you or someone else might have taken an overdose of this medicine, go to the accident and emergency department of your local hospital. Take the container with you, even if it is empty.

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: 16 Apr 2026
  • 17 Apr 2023 | Latest version

    Last updated by

    Michael Stewart, MRPharmS

    Peer reviewed by

    Sid Dajani
  • 15 Jan 2014 | Originally published

    Authored by:

    Helen Allen
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