A psychosis is a condition caused by any one of a group of illnesses that are known, or thought to affect the brain causing changes in thinking, emotion and behaviour.

People experiencing an acute stage of a psychotic illness may lose touch with reality. Their ability to make sense of thoughts, feelings and external information is seriously affected, and they may become very frightened.

Psychotic illnesses include schizophrenia and some types of depression.

During an episode of these disorders, people perceive their world differently from normal. During an episode, what they see, hear and feel is real to them, but people around them do not share their experiences.

People with psychoses might develop delusions (false beliefs of persecution, guilt or grandeur) or they may experience hallucinations where they see, hear, smell, taste or feel things which are not there. They may be depressed or elated out of all proportion to their life circumstances.

To those around them, these episodes can be threatening and perplexing. People who are not familiar with this behaviour may find it difficult to understand the fear and confusion with which people with these conditions live.

Effective medication and support from medical health professionals and counsellors mean that most people who experience a psychotic illness are able to live productive and rewarding lives.