Conditions the medication is used for: Psychoses, Schizophrenia

Other names for the medication: Sycrest®

What is this medication used for?

Asenapine (also known as Sycrest®) is mainly used to help treat the symptoms of mania. It can also be used to help the symptoms of psychosis and schizophrenia.

What is the usual dose for this medication?

The usual starting dose of asenapine is 10mg twice a day (morning and evening). This can be reduced to 5mg morning and evening if needed. The usual starting dose if given with another antipsychotic or antimanic is 5mg morning and evening. The top dose is 10mg morning and evening.

How and when should I take the medication?

How to take :

Asenapine tablets are unusual in that they must not be swallowed.

They take a bit of skill to take properly. What you should do is:

  1. Take any other medicine you might need first
  2. Dry your hands
  3. Pull back the coloured tab on the blister pack
  4. Place the tablet under your tongue and allow it to dissolve. 


  • Do not touch the tablet with wet, damp or moist hands
  • Do not push the tablet out or it will crumble
  • Do not crush the tablet
  • Do not take the tablet out until you are ready to take it
  • Do not cut the blister pack
  • Do not chew or swallow the tablet
  • Do not eat or drink for 10 minutes after taking the tablet

The reason for this is that asenapine is not absorbed or taken into the body if you swallow it, so ordinary tablets don’t work.   When to take Usually twice a day; one in the morning and one in the evening. Do not take it at the same time as food or drink.

What are the alternatives to this medication?

Please look at one of the “Handy charts” or on our website for more help and advice. There are many other antipsychotics, talking therapies and treatments for psychosis, bipolar mood disorder and other conditions.

How long does the medication take to work?

This will depend on what you are taking it for. It will usually start working within a couple of days or weeks, and the effect will build over the next few weeks. Look at one of the “Handy charts” for more help.

How long will I need to keep taking this medication for?

This will depend on what you are taking it for. Please look at one of the “Handy charts” for more help and advice.

Can I just stop taking this medication?


What should I do if I forget to take a dose or overdose?

Start again as soon as you remember unless it is nearly time for your next dose then take the next dose as normal. Do not try to catch up by taking two or more doses at once as you may get more side-effects. You should tell your doctor about this next time you meet.

Can I drink alcohol while on this medication?

If you drink alcohol while taking asenapine it may make you feel more sleepy. This is particularly important if you need to drive, cycle or operate machinery and you must seek advice on this.

Will this medication affect my other medications Including the Contraceptive pill?

Asenapine has a few interactions with other medicines:

  • If you take it with benzodiazepines (e.g. diazepam, lorazepam, temazepam) or alcohol, it will cause more sleepiness
  • The effects of asenapine can sometimes be increased by fluvoxamine
  • Asenapine can increase the effects of some treatments for high blood pressure and paroxetine   
  • Asenapine can decrease the effects of some treatments for Parkinson’s Disease e.g. Madopar® or Sinement
  • You should have no problems with "The Contraceptive Pill" and asenapine.

What sort of side-effects might I get from taking this medication?

Not all of these interactions happen in everyone. Some of these medicines can still be used together but you will need to follow your doctor's instructions carefully. There are many other possible drug interactions.


Side effect

What happens

What to do about it

VERY COMMON (more than about 1 in 10 people might get these)

Restlessness or anxiety

Being more on edge. You may sweat a lot more.

Try and relax by taking deep breaths. This often happens early on in treatment and should gradually ease off over several weeks. A lower starting dose may help sometimes.

Somnolence or sleepiness

Feeling sleepy, drowsy or sluggish. This can last for a few hours or longer after taking your dose.

Do not drive or use machinery. Ask your doctor if you can take asenapine at a different time of day or try a different dose. It should wear off after a while.

Oral hypothesia or paraesthesia

Some people get a numb tongue or mouth

Asenapine is a weak local anaesthetic. The effect on your tongue usually wears off in about 30 to 60 minutes.

COMMON (fewer than about 1 in 10 people might get these)

Movement disorders

(extra-pyramidal side effects)

Having shaky hands. Your eyes and tongue may move on their own. You may feel very restless, or stiff.

It is not usually dangerous but is a well known side effect. If it is distressing or worries you, tell your doctor. He or she may be able to give you a medicine for it e.g. an anticholinergic.


Feeling tired all the time. This may happen early on in treatment and should go away.

If you feel like this for more than a week after starting asenapine, tell your doctor. It may be possible to adjust your dose slightly. It should usually wear off.

Weight gain

Eating more and putting on weight, especially just after you start asenapine.

A diet full of vegetables, cereal and fibre may help prevent weight gain.


Feeling restless, agitated or on edge.

Try and relax by taking deep breaths. Contact your doctor if it worries you.


Feeling light-headed and faint.

Don't stand up too quickly. Try and lie or sit down if you feel it coming on. Don't drive.


Where things taste different to usual

This is quite usual for a few minutes after each dose but should wear off after that.

Postural hypotension

Low blood pressure, which can make you feel dizzy, especially when you stand up.

Try not to stand up too quickly. If you feel dizzy, don't drive. It usually wears off in a few days.


Do not be worried by this list of side effects. Some people get no side effects at all and others may get some effects that are not listed in this table. If you think you might have a side effect to your medicine, you should ask your doctor, nurse or pharmacist.



Will I need to have blood tests?

If you have bipolar disorder, schizophrenia or other long-term mental health problem, it is important to look after your physical health as well. National guidelines recommend that you should at least have your blood pressure, weight, blood glucose and blood fats (e.g. lipids, cholesterol) checked regularly. This may be done by a hospital to start with, but after that your doctor should arrange for all these to be checked at least every year. And then to do something about it if there is anything that needs treating.

Can I drive or cycle while on this medication?

You may feel a bit sleepy at first when taking asenapine. Until this wears off, or you know how asenapine affects you, do not drive or operate machinery. You should be careful as it may slow your reaction times.

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