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Overview of antipsychotics

Antipsychotics are used to treat mental health conditions such as schizophrenia, schizoaffective disorder, psychosis, mania and bipolar disorder. They're also sometimes used to treat severe depression and severe anxiety.

Your brain contains chemicals that carry messages from one part of your brain to another. One of these chemicals is called dopamine. High levels of dopamine may cause the brain to have hallucinations (hearing voices or seeing things that aren't real) and delusions (ideas or beliefs that aren't based on reality). Antipsychotic medicines reduce the amount of dopamine that can work in the brain.

If you have schizophrenia, antipsychotics can stop you having hallucinations and delusions. They can also help you think clearly.

About four out of five people with schizophrenia benefit from taking an antipsychotic. Unfortunately, antipsychotics may not always make your symptoms go away completely. But they can improve your symptoms enough to improve your quality of life.

Types of antipsychotic medicines

First generation antipsychotics include chlorpromazine, flupenthixol, haloperidol, levomepromazine and zuclopenthixol. These were the first types of antipsychotics available and have been used since the 1950s. They're also called typical antipsychotics.

Second generation antipsychotics include amisulpride, aripiprazole, clozapine, olanzapine, paliperidone, quetiapine, risperidone and ziprasidone. These medicines have been used since the 1990s. They're also called atypical antipsychotics.

Antipsychotics are available as tablets, liquids and long-acting injections.

The different antipsychotics all work as well as each other, except for clozapine which is more effective for people with schizophrenia. Because of possible side effects, clozapine needs special monitoring. It's used for schizophrenia when other treatments have not worked.

Antipsychotics do not work straight away. It may take several days or even weeks for some of your symptoms to improve. To begin with, you may find the medication helps you feel more relaxed and calmer. After one or two weeks, other symptoms should begin to improve.

Side effects from antipsychotics

Side effects of antipsychotics can be troublesome. But most people can find a medication that suits them.

The most common side effects from first generation antipsychotics are movement disorders. These may include stiffness and shakiness, restlessness (akathisia) and feeling sluggish and slow in your thinking. These are known as extrapyramidal side effects.

Second generation antipsychotics are less likely to cause these movement disorders. But they're more likely to cause weight gain and increased cholesterol in your blood. They also put you at an increased risk of developing diabetes.

Other possible side effects include dry mouth, constipation, blurred vision and dizziness.

Rarer side effects include urine retention (being unable to pee), rash and a racing heart. Also, a condition called neuroleptic malignant syndrome causing high fever, a racing heart, confusion, stiff muscles and sweating.

For more information about possible side effects from specific antipsychotics, see Comparing antipsychotics.


It's usually safe to take an antipsychotic prescribed by your doctor, but they may not suit everyone. Let your doctor know if any of the following apply to you, as you may need extra care:

Antipsychotics aren't addictive so do not cause cravings or dependence. You may get withdrawal symptoms when you stop the medication, but these can be managed.

Alcohol and other drugs

If you're taking an antipsychotic, you shouldn't drink alcohol or use marijuana, synthetic cannabis or party pills (herbal highs). Alcohol, marijuana, synthetic cannabis and party pills can lessen the effect of antipsychotics. They can also add to side effects such as poor coordination and drowsiness. Also, they often make your psychosis worse or your mood unstable.

Once you're used to your antipsychotic, you can sometimes drink small amounts of alcohol. But take care. Many road accidents occur because of mixing alcohol and marijuana with antipsychotics.

Length of treatment

Most people need to take an antipsychotic for quite a long time, often years.

For people with schizophrenia, there is good evidence that if you take your antipsychotic regularly, you'll live longer and have a better quality of life.

If you stop taking your antipsychotic, your original symptoms may return. This may happen quickly, but it can take up to six months after you stop your antipsychotic. You and your doctor should decide together when you can stop your antipsychotic.

You shouldn't stop an antipsychotic suddenly. You should stop it slowly over several weeks.

  HealthInfo recommends the following pages

On the next page: Comparing antipsychotics

Written by HealthInfo clinical advisers. Page created September 2023.


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