Antipsychotic medication

• Prescribing antipsychotic medication
• How do antipsychotics work?
• Antipsychotics licensed in the UK
• Clozapine
• Dosage
• Taking antipsychotic medication regularly
• Depot injections
• Side effects
• Movement disorders
• Driving
• Antipsychotics and older people

Prescribing antipsychotic medication

Antipsychotic drugs (which are also called neuroleptics) are prescribed to reduce the symptoms of psychosis, and to stop them re-occurring. Some can also act as an antidepressant, a mood stabiliser or a sedative, and some can reduce the symptoms of mania.

Antipsychotics are therefore prescribed when people are experiencing an episode of psychosis. Treatment with antipsychotic drugs can be given to adults without their consent under the Mental Health Act (see Mental Health Act page).

They are prescribed for people who have a diagnosis of bipolar disorder to treat episodes of mania, and if they are experiencing the symptoms of psychosis. Some types of antipsychotics are prescribed for people who have a diagnosis of bipolar disorder when they are experiencing an episode of depression. Antipsychotics may also be used to treat delusions and hallucinations that develop as part of psychotic depression.

When people start taking antipsychotic drugs, it may take a few days, or even a few weeks, before they start getting better.

Antipsychotics are prescribed for people who have a diagnosis of schizophrenia, schizoaffective disorder and bipolar disorder to prevent relapse. People who have a diagnosis of schizophrenia, schizoaffective disorder and bipolar disorder may then take antipsychotics for a number of years to stop them becoming unwell again.

All antipsychotics cause side effects (see Side effects below). However, people react differently to medication and doctors should work with each individual to try to find an antipsychotic that controls symptoms but causes the least side effects. The choice will be influenced by someone's medical history and by previous medication that an individual has tried. If one drug doesn’t work well, or causes too many unpleasant side effects, a doctor will probably change the prescription and try another drug.

Guidance from the National Institute for Health and Care Excellence (NICE) says doctors should not offer people with schizophrenia more than one antipsychotic drug at a time except for short periods – when changing to a new drug, for example. However, the National Audit of Schizophrenia 2012 (carried out by the Royal College of Psychiatrists and a number of collaborating organisations) showed that in some areas of England and Wales, it is quite common for people to be prescribed several antipsychotics to take at the same time.

You may see older drugs, first developed in the 1950s, referred to as 'typical' or 'first generation' antipsychotic medication, and more recently developed (from the 1970s onwards), ‘second generation' drugs, referred to as 'atypical' antipsychotics. Researchers say there is no real difference in the effectiveness of each one, except for clozapine, which is the most effective of all but is only prescribed to people who have not responded well to two other types of antipsychotics (see Clozapine below).

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How do antipsychotics work?

Antipsychotics boost or decrease the action of different chemicals in the brain (neurotransmitters). All antipsychotics reduce the action of the chemical dopamine. This neurotransmitter has a role in memory, attention and problem-solving, and is also involved in controlling movements. Research has shown that too much dopamine in the brain can lead to hallucinatory experiences, delusions and disordered thinking. Some types of antipsychotics also change the effect of other neurotransmitters that help govern our mood and emotions.

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Antipsychotics licensed in the UK

All medication that is available in the UK (either over the counter or on prescription) is licensed by the Medicines and Health products Regulatory Authority (MHRA). Recommended use  – only some antipsychotics are licensed to treat mania, for example – and recommended dosage is based on research evidence. Doctors can, however, choose to prescribe medication 'off licence' – for purposes that are not recommended.

Some antipsychotics are only available as 'depot injections' (see Depot injections below) and not in a form that can be swallowed.

These newer, ‘atypical’ are antipsychotics licensed for use in the UK (by the MHRA) to treat schizophrenia, psychosis or bipolar disorder. Their brand name is in brackets (British National Formulary, April 2013):

• amisulpride (Solian®)



• aripiprazole (Abilify®)

• asenapine (Sycrest®)

• clozapine (Clozaril®, Denzapine®, Zaponex®)



• olanzapine (Zyprexa®)



• paliperidone (Invega®)
• quetiapine (Seroquel® Seroquel XL®)



• risperidone (Risperdal®)

These are the older (or ‘typical’) antipsychotics licensed for use in the UK (by the MHRA). Their brand name is in brackets (British National Formulary, April 2013):

• chlorpromazine hydrochloride (Largactil®)



• flupentixol (Fluanxol®, Depixol®)



• haloperidol (Dozic®, Haldol®, Serenace®)



• levomepromazine (Nozinan®)



• pericyazine 


• perphenazine (Fentazin®)



• pimozide (Orap®)


• prochlorperazine

• sulpiride (Sulpor®, Dolmatil®)



• trifluoperazine (Stelazine®)



• zuclopenthixol (Clopixol®).

You can find out more information about each drug on the NHS Choices website where a Medicines A-Z facility allows you to look up either the generic or brand name, and find out what each drug is licensed for and its potential side effects. There is also information about each antipsychotic on the British National Formulary website. It's free to consult this website, but you have to register with an email address and password.

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Clozapine

Antipsychotic medication doesn't work for everyone. Researchers estimate up to 25 per cent of people who are prescribed antipsychotics do not get better. Health professionals say people who don't respond to antipsychotic medication are 'treatment-resistant' or call the illness 'refractory'. Sometimes people respond to antipsychotics first of all, then become treatment-resistant as the illness develops.

Research has shown that clozapine is the most effective antipsychotic for people who have a diagnosis of schizophrenia when their symptoms have not improved even though they have taken other drugs from the antipsychotic family. Clozapine is licensed to treat people with schizophrenia who have been unresponsive to, or are intolerant of, other antipsychotics. (It is also licensed to treat the symptoms of psychosis experienced by people who have Parkinson's disease).

Guidance from NICE (National Institute for Health and Care Excellence) says people who have a diagnosis of schizophrenia should be offered clozapine only after trying at least two other drugs.

Clozapine, however, doesn’t work for everyone. If clozapine makes no difference, the NICE guideline says people may be offered a second antipsychotic to take at the same time.

Clozapine can have severe, potentially life-threatening side effects. It can damage white blood cells and cause agranulocytosis – this condition means people are at high risk of serious infections. Clozapine can also cause heart problems. People who take clozapine must therefore be monitored, especially when they first start taking the drug, and have regular blood tests.

Researchers are collecting information from large numbers of people living across Europe who have been given a diagnosis of schizophrenia to see if they can work out in advance who is likely to need clozapine and who will be at risk of developing serious side effects. If researchers can find a way to predict who will be treatment resistant, doctors will be able to prescribe clozapine straightaway, rather than trying other drugs first. If researchers can also find a way to predict who will develop side effects, doctors can make treatment with clozapine safer.

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Dosage

There is no evidence that higher doses of antipsychotic medication are more effective. The NICE guideline on schizophrenia says doctors should initially prescribe a low dosage of the chosen antipsychotic and then monitor how well it is working, and its side effects. Research indicates the higher the dose, the more severe the side effects seems to be.

Antipsychotics are available as tablets or as a liquid medication. If antipsychotics are swallowed, they are taken once, twice or three times a day, depending on the drug and the dose. Some antipsychotics are available as a ‘prolonged-release’ formulation. This means the tablets are designed to release the drug continuously to provide steady blood levels of the medicine throughout the day.

The action of some antipsychotics is affected by smoking. Ingredients in tobacco smoke speed up the metabolism of clozapine, for example. Therefore, if a smoker quits, or someone starts smoking, the dose of clozapine may need to be changed.

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Taking antipsychotic medication regularly

To make sure antipsychotic medication is effective, it’s important to take it regularly and as prescribed. Research shows however, that at least half the people diagnosed with schizophrenia don’t take their drugs as recommended. Many people don’t like the idea of taking drugs every day, or forget to take them, or mistrust the doctors who prescribe them, or decide they don’t need the drugs any more because they feel well.

People also stop taking their antipsychotic medication because of the side effects, or sometimes because they don’t fully understand that they are unwell. In one survey, some people said they had stopped taking medication because they missed some of  the symptoms – hearing voices, for example.

Taking medication as prescribed is called ‘adherence’ and there is NICE (National Institute for Health and Care Excellence) guidance for health professionals about adherence. The guidance says health professionals should involved people in decisions about their medication. They should explain clearly how the proposed medication will treat the symptoms of an illness, and about the illness itself. They should explain about potential side effects and listen to people's concerns. Prescriptions should be reviewed regularly. Family members and other carers should be involved in these discussions, if the person who is being prescribed the medication agrees.

After an acute episode of psychosis, people will be encouraged to continue to take antipsychotics, even though the symptoms have passed, for one to two years. If they stop taking their drugs too soon, their symptoms may return.

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Depot injections

Antipsychotics can also be given by an injection that has long-lasting effects. These are called ‘depot’ antipsychotics and are given by injecting the drug into muscle every two to four weeks. Taking antipsychotics this way means people are less likely to forget to take their medication. Sometimes depot injections are given to people who are very unwell and may not want to take tablets regularly.

Depot injections licensed for use in the UK are:

• flupentixol decanoate (Depixol®)


• fluphenazine decanoate (Modecate®)


• haloperidol (Haldol Decanoate®)



• olanzapine embonate (ZypAdhera®)

• paliperidone (Xeplion®)


• pipotiazine palmitate (Piportil®)


• risperidone (Risperdal Consta®)


• zuclopenthixol decanoate (Cloxipol®)

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Side effects

All antipsychotic drugs have side effects. Side effects will vary from individual to individual and also depend on the dosage of the drug being taken and people's physiology or medical history. Some side effects come and go quickly – an individual may have them for a few days, or a few weeks. Others are more persistent.

Stiffness, shakiness, dizziness, dry mouth, nausea and constipation are among the common side effects of all antipsychotics. Some people no longer enjoy things that used to give them pleasure. Some drugs make people burn in the sun more easily, or make people feel as if they are slower than before. Some make people feel drowsy and make people get drunk more quickly. People who take clozapine may produce a large amount of saliva.

The older 'typical' antipsychotics cause a rise in the level of the hormone prolactin, which can lead to a lowered sex drive and breast tissue growth in both men and women, and affect women’s periods.

All antipsychotics can make people put on weight, although not everyone does.

Being on antipsychotic medication increases the risk of developing diabetes, and that risk is greater in younger people. There is also the risk of cardiovascular problems and high blood pressure. People who are on antipsychotics should have regular physical health checks and doctors should monitor for diabetes and cardiovascular disease at least once a year.

The higher the dose of antipsychotic medication, the more severe the side effects seem to be. NICE (National Institute for Health and Care Excellence) recommends doctors prescribe antipsychotics at a low dose in the first instance.

It’s important to talk to a doctor about the side effects someone is experiencing: if they are particularly severe or unpleasant, a different antipsychotic medication can be prescribed, or the dose of the medication can be altered.

NICE says doctors should take into account the likely side effects and an individual’s preferences when they are making decisions about which antipsychotic to prescribe. People should be given information about the proposed drug, including what it will achieve, its likely side effects and what alternatives there are. Family members and other carers should be involved in these discussions, if the person who is being prescribed the medication agrees.

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Movement disorders

Some people develop a ‘movement disorder' when they are taking antipsychotics. Health professionals may describe these movement disorders as 'extrapyramidal symptoms' or 'extrapyramidal side effects’.

Some people report a sense of inner restlessness that makes it hard for them to keep still and may experience involuntary body movements. This is called akathisia.

Others find they can only move slowly, or that their limbs, hands or face muscles shake or ‘tremor’. Sometimes a limb may get stuck because of abnormal muscle contractions – this is called dystonia. Other people may get oculogyric crisis, a muscle spasm that makes the eyes move suddenly.

These movement disorder side effects are similar to the symptoms of Parkinson’s disease and can be reduced by taking drugs called anticholinergics (medication prescribed to treat the movement symptoms of Parkinson’s).

People who have been on antipsychotic medication for several years sometimes develop tardive dyskinesia, a type of movement disorder that causes uncontrolled movements of the arms or legs, tongue, cheeks, jaw or face. It can make people do things like smacking their lips and pulling faces. Changing to a different antipsychotic drug straight away can help stop the tardive dyskinesia becoming permanent.

Studies have shown that the newer, atypical antipsychotics are less likely to result in this side effect when they are prescribed at a lower dose.

Clozapine is less likely to produce movement disorder side effects than other antipsychotic drugs. 

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Driving

The side effects of antipsychotic medication may impair people's ability to drive.

The DVLA should be told when people are given a diagnosis of psychosis: to find out more, visit GOV.UK – Health conditions and driving.

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Antipsychotics and older people

In the past, doctors have prescribed antipsychotics off licence to older people with dementia who had 'behavioural and psychological symptoms' (wandering, hallucinations, agitation, delusions, for example – see Older people and psychosis page.) The government has led an initiative to reduce the amount of antipsychotics prescribed for people who have dementia because the drugs can cause strokes and sudden death in older people.

Only one antipsychotic – risperidone – is licensed for the treatment of older people with dementia, though doctors may continue to prescribe other antipsychotics 'off licence'.

If antipsychotics are prescribed to older people with schizophrenia, it will usually be at a lower dose than for younger people because of the serious risks involved.