Review decision date: March 2015

Review decision: 

We checked this guideline and decided that it should not be updated at this time. For details, see the update decision and the process for deciding if an update is needed.

Next review date: December 2016

This guideline offers best practice advice on the assessment and management of people with psychosis and coexisting substance misuse.

Psychosis is a condition that affects a person’s mental state, including their thoughts, mood and behaviour. The symptoms of psychosis are:

  • hallucinations – hearing voices and sometimes seeing things that are not really there
  • delusions – having fixed beliefs that are false but which the person believes in completely.

Substance misuse is a broad term encompassing, in this guideline, the harmful use of any psychotropic substance, including alcohol and either legal or illicit drugs. Use of such substances is harmful when it has a negative effect on a person’s life, including their physical and mental health, relationships, work, education and finances or leads to offending behaviour.

This guideline was previously called psychosis with coexisting substance misuse: Assessment and management in adults and young people.

Corrections to the full version of this guideline published in March 2011

A correction was made to the full version of this guideline to incorporate references to Cleary, M., Hunt, G. E., Matheson, S. L., Siegfried, N., Walter, G. (2008) Psychosocial interventions for people with both severe mental illness and substance misuse. Cochrane Database of Systematic Reviews, Issue 1.

Your responsibility

The recommendations in this guideline represent the view of NICE, arrived at after careful consideration of the evidence available. When exercising their judgement, professionals are expected to take this guideline fully into account, alongside the individual needs, preferences and values of their patients or service users. The application of the recommendations in this guideline is not mandatory and the guideline does not override the responsibility of healthcare professionals to make decisions appropriate to the circumstances of the individual patient, in consultation with the patient and/or their carer or guardian.

Local commissioners and/or providers have a responsibility to enable the guideline to be applied when individual health professionals and their patients or service users wish to use it. They should do so in the context of local and national priorities for funding and developing services, and in light of their duties to have due regard to the need to eliminate unlawful discrimination, to advance equality of opportunity and to reduce health inequalities. Nothing in this guideline should be interpreted in a way that would be inconsistent with compliance with those duties.

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