There is no single test for schizophrenia. The condition is usually diagnosed after assessment by a specialist in mental health.

If you are concerned you may be developing symptoms of schizophrenia, see your GP as soon as possible. The earlier schizophrenia is treated, the more successful the outcome tends to be.

Your GP will ask about your symptoms and check they are not the result of other causes, such as recreational drug use.

Community mental health team (CMHT)

If a diagnosis of schizophrenia is suspected, your GP should refer you promptly to your local community mental health team (CMHT).

CMHTs are made up of different mental health professionals who support people with complex mental health conditions.

A member of the CMHT team, usually a psychologist or nurse, will carry out a more detailed assessment of your symptoms. They will also want to know your personal history and current circumstances.

To make a diagnosis, most mental healthcare professionals use a diagnostic checklist. Schizophrenia can usually be diagnosed if:

• you have experienced one or more of the following symptoms most of the time for a month – delusions, hallucinations, hearing voices, incoherent speech or negative symptoms, such as a flattening of emotions
• your symptoms have had a significant impact on your ability to work, study or perform daily tasks
• all other possible causes, such as recreational drug use or bipolar disorder, have been ruled out

Related illnesses

Sometimes it might not be clear whether someone has schizophrenia. If you have other symptoms at the same time, a psychiatrist may have reason to believe you have a related mental illness.

There are several related mental illnesses similar to schizophrenia. Your psychiatrist will ask how your illness has affected you so they can confidently confirm you have schizophrenia and not another mental illness, such as:

• bipolar disorder (manic depression) – people with bipolar disorder swing from periods of mania (elevated moods and extremely active, excited behaviour) to periods of deep depression; some people also hear voices or experience other kinds of hallucinations, or may have delusions
• schizoaffective disorder – this is often described as a form of schizophrenia because its symptoms are similar to schizophrenia and bipolar disorder, but schizoaffective disorder is a mental illness in its own right; it may occur just once in a person's life or recur intermittently, often when triggered by stress.

You should also be assessed for post-traumatic stress disorder and other conditions, such as depression, anxiety and substance misuse. 

Getting help for someone else

As a result of their delusional thought patterns, people with schizophrenia may be reluctant to visit their GP if they believe there is nothing wrong with them.

It is likely someone who has had acute schizophrenic episodes in the past will have been assigned a care co-ordinator. If this is the case, contact the person's care co-ordinator to express your concerns.

If someone is having an acute schizophrenic episode for the first time, it may be necessary for a friend, relative or other loved one to persuade them to visit their GP.

In the case of a rapidly worsening schizophrenic episode, you may need to go to the accident and emergency (A&E) department, where a duty psychiatrist will be available.

If a person who is having an acute schizophrenic episode refuses to seek help, their nearest relative can request that a mental health assessment is carried out. The social services department of your local authority can advise how to do this.

In severe cases of schizophrenia, people can be compulsorily detained in hospital for assessment and treatment under the Mental Health Act (2007).

After diagnosis

If you or a friend or relative are diagnosed with schizophrenia, you may feel anxious about what will happen. You may be worried about the stigma attached to the condition, or feel frightened and withdrawn.

It is important to remember that a diagnosis can be a positive step towards getting good, straightforward information about the illness and the kinds of treatment and services available.