“New confusion” has a name: delirium
Delirium is a sudden change in a person’s thinking, memory or alertness, usually caused by an illness, an injury, surgery or medicines. It affects 1 in 4 older people in hospital. Many families have never heard its name.
This website focuses mainly on delirium in older people outside intensive care. Much of it is relevant in an ICU, but Vanderbilt has more specific ICU information. It does not cover paediatric delirium; the Resources page links to specialist information for babies, children and young people.
Is this delirium? The common signs
Delirium appears over hours or days. The person is different from their normal self. You might notice:
Sudden confusion
Losing track of where they are, or what day or time it is. Clearly more muddled than normal.
Trouble paying attention
Conversations keep falling apart. They drift off mid-sentence or seem not to hear you.
Unusual drowsiness
Much sleepier than usual, sleeping through visits, or slow to respond. If they are hard to wake or barely responding, get emergency help now.
Restlessness or agitation
Pacing, fiddling, pulling at drips, sometimes fear or anger.
New suspicion, or seeing things
Believing others mean harm, or seeing people or animals that are not there.
Symptoms that come and go
Settled in the morning, lost by teatime. Evenings and nights are often worse.
New sudden confusion can be caused by serious illness and needs medical assessment now. Contact the urgent or emergency medical service where the person is. In England, call 999 or go to A&E. In Scotland, contact the GP urgently if open; otherwise phone NHS 24 on 111. Outside the UK, follow local health-service guidance. If the person is hard to wake, struggling to breathe, has signs of a stroke, has a seizure or head injury, or is deteriorating rapidly, call the local emergency number immediately (999 in the UK). Do not wait to see if it settles. What to do now.
Delirium is not dementia
Dementia builds slowly, over months and years. Delirium arrives in hours or days, and it usually improves once its causes are found and treated. The two conditions are often mistaken for each other, including by professionals.
If someone who already has dementia suddenly gets much worse, treat the change as possible delirium.
What you can do
Get medical help now
Sudden confusion needs medical assessment now. Who to contact, what to say, and when to call the local emergency number immediately.
Help at the bedside
You know the person’s normal self better than anyone. What to tell the team, and what actually helps, hour to hour.
Speak up for them
If you think delirium is being missed or given another name, how to raise it with staff, and the words to use.
Help them recover
Recovery is often gradual and uneven. What to expect in the weeks afterwards, and when to ask a doctor for a review.
Someone to talk to
These UK helplines can talk through what is happening. You do not need a dementia diagnosis in the family to phone them. Outside the UK, look for an equivalent dementia, carers’ or older people’s service in your country.
- Dementia UK
0800 888 6678 - Alzheimer’s Society
0333 150 3456 - Age UK
0800 678 1602 - Carers UK
0808 808 7777
Printable help to keep or share
Clear one-page guides for the ward, the kitchen drawer, or a relative who does not use the internet.
What is delirium?
The meaning, common signs, causes, treatment and what to do.
Download What is delirium? (PDF)Delirium action guide
The signs, who to contact, and when to seek emergency help.
Download the Delirium action guide (PDF)Helping at the bedside
Simple things that reduce fear and confusion, hour to hour.
Download Helping at the bedside (PDF)Questions families ask
Straight answers to the questions that come up most, including how long delirium lasts, confusion after an operation and whether delirium is a sign of dying. See all questions.