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What is psychosis?

Psychosis is a set of conditions during which young people (or adults) may experience the following types of symptoms:

Positive symptoms

  • Hallucinations (perceiving via one or more senses that something is present when it isn't, e.g. hearing voices when there's no one around, or seeing zombies).
  • Delusions (fixed false beliefs despite evidence to the contrary, e.g. believing the police are after them or that they are specially chosen by God).
  • Disorganised speech.
  • Disorganised behaviour.

Negative symptoms

  • Anhedonia (loss of interest in usual activities).
  • Amotivation (including poor self-care).
  • Alogia (loss of speech).
  • Affective flattening (not as cheerful as usual).
  • Attentional disturbance.

Cognitive symptoms

  • Reduced concentration.
  • Poor memory.

Mood symptoms

  • Depressed mood.
  • Elevated mood.
  • Anxiety.

There are many kinds of psychosis:

  • Schizophrenia is the best known, and involves the presence of the symptoms for more than six months. 
  • Schizophreniform disorder involves symptoms for one to six months.
  • Brief psychotic disorder involves symptoms from one day to one month.
  • Drug-induced psychosis is usually short-lived and triggered by drug use.
  • Psychotic disorder due to general medical condition occurs in the context of some medical problems such as brain tumours or encephalitis.
  • Bipolar disorder with psychotic symptoms involves psychotic symptoms at the peak of the manic phase or trough of the depressive phase of the illness.
  • Major depressive disorder with psychotic symptoms involves psychotic symptoms at the trough of depressive symptoms.
  • Delusional disorder involves non-bizarre delusions (no hallucinations or disorganisation of thought or actions) for more than one month. This is rare in young people and tends to occur in older adults.
  • Psychotic disorder NOS (not otherwise specified) is used to describe psychosis that doesn't fit any of the above categories or for which there is not yet enough information to make another diagnosis.

Causes and prognosis

The exact cause is unknown. Genetic, prenatal and obstetric factors have all been associated with psychosis, as have socio-economic risk factors such as adverse childhood experiences. Excessive transmission of the chemical dopamine in part of the brain is thought to be responsible for positive symptoms such as hallucinations. However, cultural explanations also apply: some Maori whanau have members who regularly hear or see spirits or ancestors and regard this as an expression of wairua (spirituality) rather than pathology.

Psychotic episodes are usually triggered by one of three things: stress, drug use and (if previously unwell) non-compliance with medication.

There has been increasing recognition that autoimmune conditions such as anti-NDMR encephalitis can cause psychosis, generally with prominent delirium and/or neurological symptoms such as seizures.

About 20% of people who have schizophrenia make a complete recovery, 40% have recurrent episodes of illness and 35% have chronic disability. There is a 50% chance of readmission within two years of the first episode, which increases with substance abuse.

People with schizophrenia have a shorter lifespan due to accidents, poor diet, medication side-effects, smoking and suicide (10%). The course over a lifetime varies for individuals, but progress in the first five years usually reflects the life course.

What can be done to help?

Early intervention is the key to improving the long term outcome for people with psychosis, especially schizophrenia. A bio-psycho-social approach via a multi-disciplinary team is usually needed for best results, as is a collaborative approach with the young person and their family. Cultural supports are essential to help distinguish between a culturally normal experience and illness and to help plan and manage treatment.

The main goal of early intervention is recovery. Recovery is not defined as the complete absence of symptoms, but living well with or without symptoms - and will have a different meaning to each person.

Treatments may include:

  • Medication
    • Antipsychotics (oral, injectable) to reduce dopamine transmission.
      These can cause side-effects such as weight gain, sedation, changes in blood pressure, diabetes and seizures, so need to be closely monitored.
    • Antidepressants, mood stabilisers.
    • Fish oils (limited evidence, currently used as adjunct to antipsychotic medication).
  • Psychological interventions
    • Cognitive behaviour therapy (CBT) to address delusions.
    • Stress management strategies.
    • Substance abuse therapies.
  • Social Interventions
    • Assistance with benefits.
    • Family support +/- therapy.
  • Vocational interventions
    • Supported employment.
    • Liaison with schools, universities, work

Young People Presenting to Paediatrics with Psychosis

  • Screening history and medical review with a focus on neurological signs and symptoms
  • Contact Consult Liaison team early in assessment. (After hours, talk to the on call Child Psychiatrist or Registrar). If symptoms seem related to a neurological condition but the patient is very agitated, joint management of Paediatrics and Psychiatry will be required. 
  • Young people with psychosis are often distressed and agitated. If possible provide a quiet space, presence of family members and calm, clear communication from staff.
  • If there are issues of risk to self or others use of the Mental Health Act Section 111 may be needed. This allows a nurse to hold a person for 6 hours pending a psychiatric assessment. In an extreme/urgent situation common law allows for staff to hold a young person who is stating that they are going to kill themselves or harm others, again pending the use of more formal legal means such as the Mental Health Act. It is always best to engage family/whanau in supporting the young person to remain for assessment if this is possible.

Did you find this information helpful?

Document Control

  • Date last published: 20 February 2017
  • Document type: Clinical Guideline
  • Services responsible: Consult Liaison Psychiatry
  • Author(s): Leah Andrews
  • Editor: Greg Williams
  • Review frequency: 2 years

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