Psychotic Disorders and Schizophrenia

Psychotic disorders are illnesses in which people experience ‘psychotic’ symptoms.   In psychotic disorders the symptoms are generally of a sufficient severity that the person has difficulty understanding what is real and what is not. Psychotic symptoms are delusions, hallucinations and disorganised thoughts, speech and behaviour   This can cause significant distress and place the person and others at risk due to abnormal beliefs and experiences. Between 1 and 4% of people with intellectual disability will experience a psychotic disorder at some point in their life. Schizophrenia is the most well-known of the psychotic disorders and most of the information about schizophrenia outlined in this module applies to the other psychotic disorders. Schizophrenia begins typically in the early to mid-twenties in men and in the late twenties in women. Psychotic symptoms are divided into positive and negative symptoms. The division is important as the symptoms occur at different stages of the illness and require different treatments. They are also associated with the outcome and prognosis of the illness (see below). Positive symptoms are called because they are additional experiences whereas negative symptoms are the loss of someone’s usual abilities and capacity.