This delirium pathway has been developed by the Scottish Delirium Association (SDA).

About this pathway

This pathway is appropriate for adult patients (18 years and over).  This pathway is not exhaustive. Other causes of delirium exist and additional or alternative assessments, investigations, management strategies or therapies may be necessary for an individual patient. Clinical judgement and decisions should be made by the appropriate responsible healthcare professional.

This pathway does not relate to alcohol or substance misuse.  If this is suspected use appropriate local pathway.

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History of acute change

Think Delirium!

Risk factors for delirium:

  • Acute illness
  • Dementia
  • Age over 70 years
  • Frailty
  • Sensory impairment
  • Polypharmacy
  • Recent anaesthetic/surgery
  • Catheterised
  • Recent discharge from acute hospital
  • Use of opioids, benzodiazepines or anticholinergics
  • Restraint
  • Depression
  • History of alcohol misuse
  • Acute or chronic pain.

Clinical suspicion of delirium or "local tool" positive (eg 4AT or CAM (see other screening and monitoring tools.

(Screening tools can be negative in the presence of delirium - use clinical judgement).

Act on acute, severe causes

For example sepsis, hypoxia, hypoglycaemia, medication intoxication.

The clinical team should take an informant history and assess capacity to consent to treatment.

If the patient is unable to consent to treatment complete an AWI Section 47 (consent to treatment) form.  Discuss a treatment plan with the patient's informant/power of attorney (attach certificate to the treatment plan).

  • An informant should be contacted to provide information about the history of cognitive impairment and functional ability, in addition to the history of current illness
  • The informant should be asked to clarify and quantify alcohol intake and recent changes to prescribed medication, falls, hydration and nutrition and identify current social support
  • If there is no informant then contact the patient's GO/social work/care home
  • Use the IQCODE or AD8 to assist with informant history
  • identify current social support.

Assess with local tool and record baseline cognitive function

  • AMT4; AMT10; MOCA; GPCOG (note- the tools accessed via these links are not CE marked)
  • Assess memory, mood, perception, sleep patterns, thinking.

Do a full physical examination including detailed neurological examination, speech assessment, and level of arousal. Look for local signs of sepsis (eg bladder, lungs, skin), constipation and consider PR exam.

Document diagnosis of delirium and suspected cases; revise as appropriate.

Medication review

  • Review age appropriateness
  • Any drugs recently started/stopped?
  • Dose changes to medication?
  • Compliance/concordance issues with medication?
  • Carefully consider ongoing needs for: opioids/benzodiazepines/antipsychotics/antispasmodics/antiepileptics/antihistamines/antihypertensives (especially if hypotension)/corticosteroids/tricyclic antidepressants/digoxin/antiparkinsonian medication
  • Avoid abrupt withdrawal of drugs with dependence potential or possible discontinuation syndrome.


Dictated by the history and examination findings:

  • U&E/LFT/FBC/Glucose/CRP
  • Calcium/Phosphate
  • Thyroid function
  • Oxygen saturation/arterial blood gases
  • ECG
  • Chest x-ray
  • Urinalysis/urine culture
  • Blood/sputum/stool culture as appropriate
  • CT brain if anti-coagulated (urgent), head injury, focal neurological signs, or persistent symptoms.


Optimise management of co-morbidity

For example:

  • Respiratory disease
  • Diabetes mellitus
  • Cardiac disease/heart failure
  • Thyroid disease
  • Parkinson's disease
  • Cerebrovascular disease.

Environmental measures

Approach patient calmly and gently from the front, etc.
  • Sleep chart; maintain daytime wakefulness with activities
  • Allow patients to mobilise as much as possible in an area which has been deemed safe given confusion/falls risk
  • Ensure glasses and hearing aids are working, treat ear wax
  • Ensure adequate diet taken, keep daily food and fluid charts
  • Ensure buzzer close to patient and respond promptly to calls
  • Listen to the patient's expression of needs
  • Reduce noise (eg monitors and alarms) and background noise
  • If language or hearing problems, consider an interpreter
  • Refer to advocacy as appropriate for example if patient detained under Mental Health (Care and Treatment) (Scotland) Act.


  • Bed moves
  • Unnecessary interventions
  • Hypoxia
  • Dehydration
  • Constipation
  • Catheterisation.

Treatment of delirium symptoms

Relax visiting times - use family to reassure and support care.  Hypoactive delirium is common in older patients.  Treat psychotic symptoms if distressing.  Consider additional staff.

If the patient's symptoms threaten their safety or the safety of others use a low dose of one medication (start low - go slow method) and review every 24 hours.

Consider the capacity to consent to treatment (AWI Section 47).

Medication for management of agitation/distress:

*Haloperidol is contraindicated in combination with QTc prolonging drugs, which makes it unlicensed and local "off label" policy should be followed).

  • Or atypical antipsychotic at a low dose, for example, risperidone 0.25mg daily, maximum 1mg in 24 hours.

Do not use if signs of Parkinsonism or Lewy body dementia.

If antipsychotics are contraindicated (as above):

  • Lorazepam 0.5-1mg orally (max 2mg/24 hours); midazolam 2.5mg IM (max 7.5mg/24 hours).  Younger patients may need higher drug doses.

Medical and nursing management

Treat underlying causes:

  • Infection/sepsis, urinary retention, constipation, hypotension, pain, dehydration, hypoxia, hypoglycaemia, hyponatraemia
  • Ensure diagnosis to patient and carer and provide a leaflet
  • Use Butterfly scheme / "Getting to know me"/ "This is me" / "Forget me not"
  • Assess and monitor pain (eg by using the Abbey Pain Scale or similar)
  • Consider if swallow safe.

Note: There are often multiple causes of delirium but in up to 30% of cases no cause is found.

Triggers for referral to liaison psychiatry

  • Severe agitation or distress not responding to standard measures above
  • doubt about the above diagnosis
  • if detention under the Mental Health Act is being considered.

Psychiatric services may also hold useful information on background cognition and mental health.

Repeat delirium screening

Repeat delirium screening when clinically indicated until two successive daily negatives.

Improvement may also be seen with improving cognition or sleep pattern.

Is the patient improving?

Patient improving:

  • Reduce and discontinue antipsychotic treatment
  • Repeat cognitive assessment
  • Consider post-delirium distress (eg recall of delusional states)
  • Encourage patients to share their experience with healthcare staff.

Patient not improving:

After one week of severe delirium, refer to the appropriate local specialist.

Delirium can persist for weeks or months after the cause is treated.

Ongoing cognitive impairment?

  • Document diagnosis of delirium on discharge letter to GP
  • High risk of recurrent delirium requiring prompt treatment
  • Follow cognitive impairment pathway.

No ongoing cognitive impairment?

  • Document diagnosis of delirium on discharge letter to GP
  • High risk of recurrent delirium requiring prompt treatment
  • Increased risk of dementia in the future of older people.

Editorial Information

Last reviewed: 31/10/2018

Next review date: 28/02/2025

Author(s): Scottish Delirium Association.

Version: 1.03