Skip Ribbon Commands
Skip to main content

Decoding Delirium

Understanding this condition and how to care for someone affected by it.

Sudden changes in concentration, memory and orientation. Unexplained changes in mood, personality and behaviour. These are tell-tale signs of delirium — a sudden change in mental state, occurring in a matter of hours, or days, that results in a person being in an ‘acute confusional state’.

Not to be mistaken for depression, or dementia which develops over time, delirium is a fluctuating and changing condition that affects people’s brains for varying periods. It occurs when a person is medically unwell, and if left untreated, can result in poor health-related outcomes.

Common causes

Delirium can be traced to several causes, such as acute medical conditions, stroke, infections, head injuries, post-surgery effects, or side-effects of medications. Often, there is more than one cause and medical tests may be needed to be carried out to identify them.

Who’s at risk

Delirium generally affects high-risk groups such as seniors aged 65 years and older. Persons with dementia are at particular risk. Having more than one illness, severe illness, a previous history of delirium, poor hearing or sight, a history of alcohol misuse and depression are other risk factors.


If someone suspects that their loved one is showing signs of delirium, the first thing to do is see or alert a doctor or nurse immediately. They will conduct relevant tests to make an accurate diagnosis, and manage any causes or triggers that can be treated.

Multi-faceted care

At Changi General Hospital (CGH), patients who are at risk of developing delirium are systematically identified and screened. Once delirium is recognised, holistic management of the underlying causes is carried out together with a multi-component care bundle. This consists of standardised protocols for the management of risk factors for delirium, such as cognitive impairment, dehydration, constipation, pain, immobility and sleep deprivation.

The CGH care team also encourages patients to ambulate (move), with necessary assistance to avoid falls, promotes a regular night-day and sleep-wake cycle when possible, maintains a reassuring and familiar environment with familiar objects or photos from home while avoiding overstimulation — for instance, minimising multiple visitors or loud noises, which can worsen delirium.

In addition, CGH has a Dementia and Delirium Outreach Team (DDOT), an integrated service run by an inter-disciplinary team that offers individualised management of hospitalised seniors aged 65 and above with moderate to severe disturbed behaviour associated with delirium and/or dementia.


To treat delirium, the cause has to be addressed. For example, an infection may be treated with antibiotics, or constipation with a regular laxative. It is important to identify and address all the contributing causes.

It takes some time for persons with delirium to recover even after the underlying causes are treated. Those who are also suffering from dementia may take a longer time to recover. Ongoing vigilance and prompt medical attention are needed to prevent poor health-related outcomes. To reduce the risk of developing delirium, regularise sleep, reduce noise, promote mobility, manage pain, avoid constipation, encourage eating and drinking, and discuss the medication regime with doctors.


Someone with delirium is easily distracted or confused, has difficulty concentrating and following conversations, and may not remember what has happened.

Those with hyperactive delirium may get restless, become agitated or aggressive, and may even hallucinate. Some may become paranoid.

Those with hypoactive delirium are unusually drowsy, withdrawn, or quiet. There may be changes in appetite or mobility.

Mixed delirium is a combination of symptoms of both hyperactive and hypoactive delirium. One may also switch between the two states





Clinical Assistant Professor Bharathi Balasundaram, Senior Consultant, Department of Psychological Medicine, Changi General Hospital

Decoding Delirium