• Antipsychotic medications work by altering brain chemistry to help reduce psychotic symptoms like hallucinations, delusions and disordered thinking.
  • They can also help prevent those symptoms from returning.

Antipsychotic medications don't ‘cure’ psychosis, but they are often effective in reducing and controlling many symptoms, including: 

  • delusions and hallucinations, such as paranoia and hearing voices
  • anxiety and serious agitation, for example from feeling threatened
  • incoherent speech and muddled thinking
  • confusion
  • violent or disruptive behaviour
  • mania.

Rather than removing these symptoms completely, sometimes anti-psychotic medication may prevent the symptoms from being so intrusive and intense – helping the person feel more stable and productive.  


A person with psychosis might:

  • see or hear things (hallucinations) that are not there, or 
  • have ideas or beliefs that do not match reality (delusions). 

These may be called ‘psychotic symptoms’, a ‘psychotic episode’ or a ‘psychotic experience’.

Psychotic symptoms can be part of conditions such as schizophrenia, schizoaffective disorder, certain personality disorders and bipolar disorder. Some people can have psychotic symptoms without having any of these conditions.

Antipsychotic medications and psychotic symptoms

During a psychotic episode, the person may experience delusions, hallucinations or thought disturbances. Antipsychotic medications work to minimise or stop these symptoms. 

There are many different types of antipsychotic mediations. These works in different ways. People who begin taking antipsychotic mediations are usually closely monitored by their doctor for the first few weeks. The doctor will be checking for signs of improvement as well as side effects.

A person usually begins to feel some improvement within six weeks of starting to take antipsychotic medication. However, it can take several months before they feel the full benefits. It is not possible to predict which medication will work best for a specific person. You might need to try a few before you find the right one for you.

Antipsychotic medications and other illnesses

Some antipsychotic medications may also be used to treat:

  • severe anxiety
  • physical problems, such as persistent hiccups, problems with balance and nausea 
  • agitation
  • problems with mood, thinking and socialising
  • mania 
  • psychotic symptoms of depression
  • postpartum psychosis.

How do antipsychotic medications work?

It is thought that dopamine is a contributing factor to the development of psychosis. Dopamine is one of the many chemicals present in the brain that carry messages from one part of the brain to another. 

Dopamine, among other things, is involved in how a person:

  • knows that something is significant, important or interesting;
  • experiences pleasure and reward
  • feels motivated.

It is also involved in the control of our muscles and movement.

It is thought that high levels of dopamine may cause the brain to function differently and may cause the symptoms of psychosis.

Antipsychotic medications reduce the amount of dopamine in the brain or restore the balance of dopamine with other chemicals in the brain.

Types of antipsychotic medications

There are two types of antipsychotic medications:

  • typical, ‘first generation’ (older) antipsychotics – these medications have been used since the 1950s
  • atypical, ‘second generation’ (newer) antipsychotics – these medications have been used since the 1990s.  

While both generations are effective, the newer medications in general have several advantages over the older ones, including:

  • fewer side effects such as trembling or stiffening of muscles
  • less risk of developing ‘tardive dyskinesia’ – uncontrolled movement of the person’s mouth, tongue and, sometimes, other parts of the body
  • may help improve overall mood, thinking and motivation. 

Although newer antipsychotic medications are more commonly used than the older ones, some people find that the older medications suit them better.

Delivery of antipsychotic medications 

Most antipsychotic medications are taken in tablet form, but can also be taken in syrup or liquid form, or as an injection (known as a ‘depot’).  

Depot injections contain the same medications as those found in pill or liquid form. They are given in a ‘carrier liquid’ that releases the medication slowly, so it lasts a lot longer. This can occur over several weeks. Not all antipsychotics are available as depot injections.

Depot injections might be helpful where:

  • a person has difficulty remembering to take their medication regularly or may take the wrong dose
  • a person might have difficulty swallowing medication in tablet form
  • the person would prefer not to have to think about taking medication every day 
  • medication might be a condition of a court community-treatment order.

It is important to discuss with your doctor the different treatment options available, and which of them might be the best for you.

Whichever delivery method you choose, do not suddenly stop taking antipsychotic medication without speaking with a mental health professional, as psychotic symptoms may return.

Side effects of antipsychotic medications

Antipsychotic medications should come with a leaflet about the specific medication prescribed. This includes information on side effects and what to do if they are overwhelming.

Possible side-effects of antipsychotics include: 

  • dry mouth
  • dizziness
  • weight gain that can lead to diabetes
  • blurred vision 
  • movement effects (for example, tremor, stiffness, agitation) 
  • sedation (for example causing sleepiness or low energy) 
  • loss of menstrual periods in women
  • fluid retention
  • dry mouth
  • sexual problems
  • headaches.

It is important to remember that the same medication can affect different people in different ways. Not everyone will have the same unwanted side effects.  

Managing medication side effects 

If you are worried about any side effects you may be experiencing, talk to your treating doctor. To manage or reduce side effects, your doctor may:

  • change the dose of the medication
  • prescribe a different medication
  • suggest that you take the medication at a different time of day
  • try non-medication intervention to reduce side effects. For example, diet and exercise programs can be helpful in addressing weight gain.

Where to get help


More information

Mental illness

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Mental illness explained

Types of mental illness

Living with mental illness

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This page has been produced in consultation with and approved by: SANE Australia

Last updated: October 2019

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