This information may be helpful if you have been prescribed antipsychotic medication, are a friend or relative of someone who has, or you just want to find out about antipsychotic medication.


This webpage provides information, not advice. You should read our full disclaimer before reading further.

This information reflects the best available evidence at the time of writing. We aim to review our mental health information every three years, and update critical changes more regularly.

©  April 2015 Royal College of Psychiatrists 

They are a range of medications that are used for some types of mental distress or disorder - mainly schizophrenia and manic depression (bipolar disorder). They can also be used to help severe anxiety or depression.

  • The experience of hearing voices (hallucinations).
  • Ideas that distress you and don't seem to be based in reality (delusions).
  • Difficulty in thinking clearly (thought disorder).
  • The extreme mood swings of manic depression/bipolar disorder.
  • Some can help with severe depression.

They all affect the action of a number of chemicals in the brain called  neurotransmitters – chemicals which brain cells need to communicate with each other. Dopamine is the main neurotransmitter affected by these medications. It is involved in how we feel:

  • that something is significant, important or interesting;
  • satisfied;
  • motivated.

It is also involved in the control of muscle movements.

If parts of the dopamine system become overactive, they seem to play a part in producing hallucinations, delusions and thought disorder.

Although these medications were known as ‘major tranquillisers’ in the past, they are not designed to make you calmer or sleepy – so they are not the same as medications like Valium or sleeping tablets. 

The basic aim is to help you feel better, without making you feel slowed down or drowsy. However, high doses may well make you feel too sleepy or 'drugged up'.

They can be used in higher doses if you become very overactive, agitated or distressed - but this should usually only be for a short time.

For the past 10 years or so doctors have talked about two different groups of antipsychotics:

  • ‘Typical’ - the older drugs
  • ‘Atypical’ - the newer drugs

Recent large independent research studies - not paid for by the drug companies – suggest that the new drugs are not really different – but are, in some situations, easier to use.

Most antipsychotics seem to be equally as good at controlling psychotic symptoms – Clozapine is the exception and is described later.

Even so, individuals react differently to them, particularly with the side-effects. We cannot predict how well a particular person will respond to a particular drug – even whether a newer, or older drug, will be more helpful.

It can often take some time, negotiation and ‘trial and error’ to find the best antipsychotic for a particular person.

Older antipsychotics

These first appeared in the mid-1950s. These older drugs are often called ‘typical’ or 'first-generation' antipsychotics. They all block the action of dopamine (see above), some more strongly than others.Side-effects include:

  • stiffness and shakiness, like Parkinson’s disease
  • feeling sluggish and slow in your thinking
  • uncomfortable restlessness (akathisia)
  • some can affect your blood pressure and make you feel dizzy
  • problems with your sex life
  • problems with breast swelling or tenderness.

If you have any of these symptoms, you are probably on too high a dose. It should usually be reduced until the side-effects disappear.

If you do need a higher dose to stay well, these side-effects can be controlled with anticholinergic drugs - used to treat Parkinson's disease. Orphenadrine and Procyclidine are the two most commonly used anticholinergics in the UK.

A longer-term problem is tardive dyskinesia (TD for short) – continual movements of the mouth, tongue and jaw.  This affects about 1 in 20 people every year who are taking these medications.

Some older 'typical' antipsychotics

Tablets Trade name  Usual daily dose (mg)  Max daily dose (mg) 
 Chlorpromazine  Largactil  75-300 1,000 
 Haloperidol  Haldol  3-15  30 
 Pimozide  Orap  4-20  20
 Trifluoperazine  Stelazine  5-20  
 Sulpiride Dolmatil   200-800  2,400

Newer antipsychotics

Over the last 10 years, newer medications have appeared. They still block dopamine, but much less so than the older drugs.

They also work on different chemical messengers in the brain (such as serotonin) and are often called ‘atypical’ or ‘second-generation’ antipsychotics.

This is misleading - they have many of the same effects as the older drugs.

The newer antipsychotics are also being used to help treat some people's depression.

There is growing evidence that this can be effective when combined with an antidepressant. Your psychiatrist will talk to you if this is an option to consider.

Side effects 

  • Sleepiness and slowness
  • Weight gain
  • Interference with your sex life
  • Increased chance of developing diabetes.
  • Some can affect your blood pressure and make you feel dizzy.
  • In high doses, some have the same Parkinsonian side-effects as the older medications (stiffness of the limbs).
  • Long-term use can produce movements of the face (tardive dyskinesia) and, rarely, of the arms or legs.

Compared to the older drugs they seem:

  • less likely to cause Parkinsonian side-effects (see above)
  • less likely to produce tardive dyskinesia.
  • more likely to produce weight gain
  • more likely to produce diabetes
  • more likely to give you sexual problems.

They may also help 'negative symptoms' (poor motivation, lack of interest, poor self-care), on which the older drugs have very little effect.  Some people find the side effects less troublesome than those of the older medications.

Some of the newer 'atypical' antipsychotics

Tablets Trade name  Usual daily dose (mg)  Max daily dose (mg) 
 Amisulpride Solian  50-800   1,200
 Aripiprazole  Abilify  10-30  30
 Clozapine  Clozaril  200-450  900
 Olanzapine  Zyprexa  10-20  20
 Quetiapine  Seroquel  300-450  750
 Risperidone  Risperdal  4-6  16


Clozapine seems to be the only antipsychotic medication which works better than any of the others. It also seems to reduce suicidal feelings in people with schizophrenia.

It has many of the same side-effects as other newer antipsychotics, but can also make you produce more saliva.

It is different in that it seems to have very little, if any, effect on the dopamine systems which control movement, and so causes hardly any of the stiffness, shakiness or slowness that you can get with other antipsychotics.

Although it does tend to make you drowsy, some people are prepared to put up with this because it makes them feel less sluggish than on the older antipsychotics.

It also does not seem to produce the longer-term problem of tardive dyskinesia and can be used to help relieve this.


The main drawback is that it can affect your bone marrow, leading to a shortage of white cells. This makes you vulnerable to infection. If this happens, the medication is stopped at once so that the bone marrow can recover.

So, if you take Clozapine you will need weekly blood tests for the first 6 months and 2 weekly blood tests after that. It can also cause weight gain,  constipation, over-production of saliva and make epileptic fits more likely.

These problems mean that Clozapine is usually only suggested after at least two other antipsychotics have been tried. It is a difficult drug to monitor and can be difficult to take, but some people find that overall it gives them a much better quality of life.

The word ‘depot’ means that the medication is given not as tablets, but as an injection every 2 to 4 weeks. It releases the medication slowly over this time. The effects are generally the same as medications taken by mouth.

What's good about having a depot injection?

Unlike tablets, you only have to think about it once in a while. As there is someone else to remind you, it can be easier to remember to take than tablets.

What's bad about having depot injections?

  • Nobody likes having injections – even though the pain is slight and doesn't last long.
  • It takes a long time to know the effect of changing the dose. If the dose is changed, you may not know what the effect of this change is for several weeks or months – it can take 4 injections or so for the change to work its way through.
  • If a particular dose is giving you side-effects, lowering it may make little difference for several weeks.

How are the injections given?

  • A nurse will give you the injection. There is usually no-one else in the room - just you and the nurse.
  • The first injection is usually a small dose of the medication to check that it does not give you any side-effects.
  • If there are no problems then, a week or so later, you can start having regular injections at a higher dose.
  • After each injection, the medicine will stay in your body for several weeks.
  • The interval between injections is usually between 2 and 4 weeks

Where can you have the injections done?

You can usually decide yourself where to have the injections. This might be:

  • at your local GPs' surgery
  • at a community mental health centre
  • at a special out-patient clinic
  • at your home, when a nurse visits you.

Some common depot antipsychotics

Depot injections

Trade name

Normal 2-weekly dose

Usual max.


Haloperidol decanoate




4 weeks

Flupenthixol decanoate




2 weeks

Fluphenazine decanoate




2 weeks

Pipothiazine palmitate




4 weeks

Zuclopenthixol decanoate




2 weeks


Trade name

Normal 2-weekly dose

Usual max.

How often


Risperdal Consta



2 weeks

There is work in progress to make new depot medications from the second generation antipsychotics and these may be available soon.

How well does medication work?

  • About 4 in 5 people get help from them. They control the symptoms, but do not get rid of them. You have to go on taking the medication to stop the symptoms from coming back.
  • Even if the medication helps, the symptoms may come back. This is much less likely to happen if you carry on taking medication, even when you feel well.

This depends on a number of factors.


If you have had just one episode of schizophrenia, you have roughly 1 in 4 chance that your symptoms will not return after you get better. So you may well not need to carry on taking an antipsychotic.

For most people with schizophrenia, the symptoms will continue or come and go over the years. Some things to consider are:

  • You may find that antipsychotic medication takes your symptoms away completely. It's more likely that they will just make the symptoms less intense and easier to cope with.
  • As with any medication, you have to balance the help you get from it, against any side-effects it gives you.
  • For many people the symptoms seem to come and go for no obvious reason – so there may be times when it is more helpful to take such medication, and times when you don't need it so much.
  • If you have had more than one period of psychotic symptoms and stop the medication, the symptoms will usually return within 6 months.
  • There is evidence that if major long-term problems are going to develop they do so in the first 5 years or thereabouts. So your doctor may feel that it is important to use medication to try and keep you well through these early years.

Bipolar disorder

Bipolar disorders will almost always return although, during the first episode, it is hard to predict how often this will happen.

What happens if I stop antipsychotic medication?

The symptoms will usually come back - not immediately, but usually within 3 – 6 months.

How do I stop taking it?

If you decide you want to stop taking an antipsychotic, talk it over with your psychiatrist. You and the psychiatrist may disagree about this, but there is a way that can help both sides to feel happier. You can:

  • make a list of feelings/thoughts/behaviours that might warn you that your symptoms are returning. The pattern of symptoms is often very similar from one episode to another.
  • make a similar list – with someone you trust and who knows you well - of what other people might notice if your symptoms start to return.

Antipsychotics are not addictive, but your body does get used to having them in its system and stopping them suddenly may make you feel physically and/or mentally unwell. If you decide to stop, reduce the medication gradually, giving each reduction a few weeks to take effect.

This means that your symptoms are not likely to suddenly return. If they do start to get worse again, you can think about what to do next while you are still well.

If you do stop medication completely, keep in touch with your psychiatrist or mental health worker, even if you have been well for a few months without medication.

The evidence is very clear that nothing else works as well as antipsychotic medications in the treatment of the more troublesome symptoms of psychotic illnesses. 

For many people, antipsychotics alone are not enough to get them back to a full and active life. Other ways of helping will usually be added to antipsychotic treatment rather than replacing it. These include:

Cognitive behaviour therapy (CBT)

This is a talking treatment which can be helpful if you have distressing psychotic symptoms. It can help you to control them and to feel less distressed by them.  It can also be used to help you identify if your symptoms are returning again.


This helps you to find out more about your disorder, how to manage it and the treatments available. The purpose is to help everyone (including families) understand the illness better so that they can cope better and be more supportive.

Family therapy

Professionals will meet with the whole family. The aims are:
  • to reduce tensions between the person with a psychiatric illness and those who care for them;
  • to give the family practical ways of coping with everyday problems.

We know that these tensions can make it more likely that the symptoms will get worse.

Hearing voices groups

People who have similar experiences of hearing voices get together to discuss their experiences and how they cope with them.

Not all of these are available in all areas, and they may not be helpful for everybody – if you feel that one of these might be helpful for you, talk it over with your psychiatrist or mental health worker.

There are no antipsychotics that are clearly 'better' than any others. Clozapine is more effective, but has potentially dangerous side-effects and means that you have to have regular blood tests.

NICE guidelines (England and Wales) suggest that one of the newer antipsychotics should be tried first and then one of the older ones, depending on how well the medication works for you, and any side-effects they give you.

The best thing is to weigh up the benefits and risks of the different medications with your psychiatrist. Write down the things you are worried about before the appointment so that you don't forget anything important.

For a full list of side effects please visit and type in the name of the medicine in the 'Search for:' section at the top of the page.

Hearing Voices Network

Mind and Mind Cymru

Mindinfoline: 0845 766 0163. Mind provides information and advice, training programmes, Mind in your area, grants and more.

National Schizophrenia Fellowship (Scotland): works to improve the wellbeing and quality of life of those affected by schizophrenia and other mental illness, including families and carers.

Rethink: National voluntary organisation that helps people with any severe mental illness, their families and carers.

Shine: supporting people with mental ill health

Saneline: Helpline: 0845 767 8000. A national mental health helpline offering emotional support and practical information for people with mental illness, families, carers and professionals.



This information was produced by the Royal College of Psychiatrists' Public Education Editorial Board  and reflects the best available evidence at the time or writing.

  • Series Editor: Dr Philip Timms
  • Expert Review: Dr Michael Lacey
  • Patient and carer input: members of the Public Education Editorial Board