Delirium is an acute brain dysfunction that develops over hours to days.
It is common in hospital, especially in people with dementia, and needs a search for the cause.
Key concepts
- Onset is sudden and symptoms fluctuate through the day
- Infection, dehydration and medicines are common triggers
- Family presence helps reorient the patient
Symptoms and signs
- Confusion about time, place or people
- Seeing things that are not there, restlessness
- Unusual drowsiness or reversed sleep cycle
Causes
- Urinary or chest infection
- Dehydration, low sodium or low sugar
- Sedatives, pain medicines or alcohol withdrawal
Risk factors
- Age over 65 and dementia
- Surgery such as hip fracture
- Poor vision or hearing
Evidence-based management
- Urgent medical evaluation for the underlying cause
- Orientation: clock, calendar, glasses, hearing aids, familiar faces
- Good hydration, sleep at night, early mobilisation
- Medicines only for severe distress or danger
When to seek professional help
- Sudden confusion, weakness or slurred speech — go to an emergency department now
- Confusion during fever or after surgery — inform the treating doctor
- Families can book an online consultation and join the call with the elder
Frequently asked questions
Is delirium the same as dementia?
No. Delirium is sudden and often reversible; dementia develops slowly over months to years.
How long does delirium last?
Usually days, but recovery can take weeks in frail elders.
Medical references
Guidelines and official sources used for this article.
- Delirium: prevention, diagnosis and management (CG103). NICE, UK, 2010.
- ICD-11 for Mortality and Morbidity Statistics. World Health Organization.
- Author
- Dr. Kuldeep Budania, MBBS, MD Psychiatry
- Medical reviewer
- Dr. Kuldeep Budania, MD Psychiatry
- Last reviewed
This article is for general information and is not a substitute for personal medical advice.
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