Psychosis is a syndrome observed in a number of mental illnesses such as schizophrenia, severe depressive episodes and mania. Some illicit drugs and alcohol can also cause psychotic symptoms, or they may result from medication (anti-Parkinsonian) and consequences of medical illnesses.

Examples of psychotic symptoms include delusions, which are unshakeable beliefs that are false, maintained despite lack of proof or evidence to the contrary, and which are not culturally-bound or accepted by their religious background. Beliefs tend to be of a persecutory (being followed), conspirational (part of a conspiracy), or referential (others talking about them) nature, of grandiosity (being someone of great importance), or bizarre (where the content is so non-credible as for the clinician not have to require evidence to disprove it).

Hallucinations are false perceptions, either visual, auditory, tactile, gustatory or olfactory, which are registered by the individual in the absence of an object giving rise to them. The experience of an hallucination strongly suggests the presence of an abnormal mental state and some types of hallucinations are only seen in certain disorders.

The ability to construct thought patterns is disturbed giving rise to disorders of thought. The individual may jump from topic to topic without clear association between the two.

Passivity experiences involve the belief that thoughts are being implanted into or taken from one’s mind, or that they are being ‘broadcast’ through some media, or that emotions and actions are being controlled by something/ someone external to themselves.

Psychotic symptoms are often accompanied by changes in mood, which may be excessively high or depressed, and in movement that can range from excessive activity to immobility. A person may also have the experience of their thoughts being too fast or slow. This can lead to them having difficulties expressing ideas or maintaining a single spoken topic. In some cases, for example in schizophrenia, the sufferer’s personality, social and vocational functioning may be disturbed beyond the period of time that the patient suffers psychotic symptoms. On other occasions, the patient may experience more drawn out deficits in motivation, volition, mood and poverty of thought that may further impair overall functioning.

An individual may experience a selection or all of the symptoms listed. Common to all of the symptoms is that they can be highly distressing for sufferers and their families. Because of the distressing content and nature of the symptoms, people with psychotic illnesses are sometimes at risk of behaviour that may cause harm to themselves or others.

 Depending on the severity of the symptoms, people with psychotic illnesses may receive inpatient or outpatient treatment. Anti-psychotic medication is the first-line treatment and is necessary in almost all cases where an individual suffers these symptoms e.g. psychotic depression, mania with psychosis and schizophrenia. Only in the rare occasions when the symptoms have resolved spontaneously after a few hours or days can the clinician consider not starting medication. Antipsychotics act on neurotransmitter systems to re-establish the appropriate balance in, for example, an overactive dopamine system.

Cognitive behaviour therapy (CBT) has been shown to be an effective means of helping people to cope with psychotic symptoms when these are not entirely responding to medication alone. For example, they may learn to recognise that voices they hear cannot harm them or to question beliefs that they are at risk or being persecuted. It is sometimes necessary to rehabilitate patients with severe psychotic disorders to re-learn social and vocational skills.