Types of psychosis

When someone has psychosis, a particular psychotic illness may be diagnosed. Diagnosis means identification of an illness by symptoms.  A person's diagnosis will depend on what may have triggered the illness and how long the symptoms last.
When someone experiences psychosis for the first time, it can be difficult to make an exact diagnosis, because many of the factors underlying the illness may be unclear.
Nevertheless, it is helpful to understand some of the diagnostic labels you might hear.

Drug-induced psychosis

Using or withdrawing from drugs and alcohol can cause psychotic symptoms.  Sometimes these symptoms will rapidly disappear as the substance wears off.  In other cases, the illness may last longer, but begin with drug-induced psychosis.

Organic psychosis

Psychotic symptoms may appear to due to a head injury or a physical illness that disrupts the brain functioning, such as encephalitis, AIDS or a tumour.  There are usually other symptoms present, such as memory problems or confusion.

Brief reactive psychosis

Psychotic symptoms may arise suddenly in response to a major stress in someone's life, such as a death in the family or other important change of circumstances.  Symptoms can be severe, but the person makes a quick recovery in only a few days.

Schizophrenia

Schizophrenia refers to an illness in which the changes of behaviour or symptoms have been present for a period of at least 6 months.  Again, symptoms, severity and length of illness vary from person to person.  Contrary to previous beliefs, schizophrenia is a fairly common illness (one in 100), and many people with schizophrenia lead happy and fulfilling lives.

Schizophreniform disorder

This diagnosis is usually given when symptoms have lasted for less than 6 months.

Bipolar disorder (manic depression)

Bipolar disorder is a 'mood disorder'.  Psychotic symptoms can appear as part of a more general disturbance in mood, which is characterised by extreme highs (mania) and lows (depression).  Psychotic symptoms tend to fit with the person's mood.  If they are usually excited or happy, they may believe they are special and can perform amazing feats.  If they are depressed, they may hear voices telling them to commit suicide.  Not everyone who has biploar disorder experiences psychotic symptoms.

Psychotic depression

Also a 'mood disorder'.  This is severe clinical depression with psychotic symptoms but without periods of mania or 'highs' occuring during the illness.

Schizoaffective disorder

This diagnosis is made when the clinical picture is not 'typical' of either a mood disorder or schizophrenia, but the person has concurrent or consecutive symptoms of both illnesses.

Information in this section is adapted from the Early Psychosis Prevention and Information Centre (EPPIC), Melbourne, Australia, Causes of Psychosis.