Delirium is a sign of acute illness until proven otherwise. Hunt for and treat the cause. Avoid benzodiazepines unless the cause is alcohol or benzodiazepine withdrawal, or seizures.
Recognise (4AT or CAM)
- Acute onset and a fluctuating course
- Inattention (for example, months of the year backwards)
- Disorganised thinking or an altered level of consciousness
- Hyperactive, hypoactive (often missed) or mixed
Causes (PINCH ME)
- Pain, Infection, Nutrition, Constipation
- Hydration, Medication (new drugs, opioids, anticholinergics, withdrawal)
- Environment, plus urinary retention, hypoxia, metabolic disturbance
- Alcohol or benzodiazepine withdrawal
At risk / prevention
- Age, dementia, acute illness
- Orientate, sleep, hydrate, mobilise
- Review medications
Hyperactive or hypoactive
- Fluctuating confusion, inattention (4AT)
- Find and treat the cause
- Non-drug measures first
Severe distress / risk
- Severe agitation, risk to self or others
- Short-term low-dose haloperidol (caution)
- Avoid in Parkinson's and Lewy body
Management
1
1. Find and treat the cause
Examine and investigate: observations, bloods, glucose, urine, ECG, and review the drug chart. Treat infection, pain, retention and constipation; correct hypoxia and electrolytes.
Examine and investigate: observations, bloods, glucose, urine, ECG, and review the drug chart. Treat infection, pain, retention and constipation; correct hypoxia and electrolytes.
↓
2
2. Non-drug measures first
Reorientate, ensure glasses and hearing aids, promote sleep and mobility, keep continuity of staff, and involve family.
Reorientate, ensure glasses and hearing aids, promote sleep and mobility, keep continuity of staff, and involve family.
↓
3
3. Agitation
Only if the patient is a danger to self or others and de-escalation has failed: a short course of low-dose haloperidol (avoid in Parkinson's or Lewy body dementia; use lorazepam instead). Review daily.
Only if the patient is a danger to self or others and de-escalation has failed: a short course of low-dose haloperidol (avoid in Parkinson's or Lewy body dementia; use lorazepam instead). Review daily.
↓
4
4. Document and follow up
Compare with baseline cognition using collateral history. Delirium can persist: arrange follow-up and explain to family.
Compare with baseline cognition using collateral history. Delirium can persist: arrange follow-up and explain to family.
Higher-risk patients
- Older age, dementia, frailty
- Sensory impairment, severe illness, surgery
- Polypharmacy
Pitfalls
- Missing hypoactive delirium
- Sedating instead of treating the cause
- Antipsychotics in Parkinson's or Lewy body dementia
- Labelling as dementia without collateral
MedPrep - www.medprep.uk - Educational revision aid only. Not clinical guidance. Doses are adult examples; check the BNF, current guidelines and local policy, and seek senior advice. Nov 2026