Who Is at Risk for Delirium?

By Wheeler, Brooke 
April 30, 2017

Who Is at Risk for Delirium?

Delirium is a sudden change in a person’s mental state and ability to think clearly. It happens most often in older people who have a serious illness. There is a greater risk if the person has dementia. But delirium can happen at any age. And it does not always happen in someone with a serious illness.

Delirium is seen as an emergency. It needs to be looked at by a healthcare provider right away.

What raises a person’s risk?

Delirium can happen while a person is being treated for an illness or other serious health condition. It can also happen after surgery. The person may be in a hospital or nursing home. Or he or she may be at home. Delirium often goes unrecognized in older adults.

A person is at risk for delirium if he or she has one or more of these:

  • Current dementia or cognitive impairment

  • A past episode of delirium

  • Depression

  • Age 75 or older

  • Any serious illness, such as cancer, heart attack, or metabolism problem such as those tied to kidney or liver failure

  • Been admitted to intensive care in a hospital

  • Physical restraints

  • Been using or is withdrawing from drugs or alcohol

  • Past or current brain injury or disease

  • A bladder catheter

  • An infection

  • Broken bones, especially those that need orthopedic surgery

  • Sleep problems because of light, noise, or other disruptions

  • Constant or severe pain that is not well-managed

  • Dehydration

  • Poor nutrition

  • Poor eyesight or hearing

  • Several tests or treatments in a short time

  • Not being able to move or pain with movement

  • Recent surgery with anesthesia

Medicines that raise risk of delirium

Certain medicines can raise a person’s risk of having delirium. They include:

  • Prescription medicines. This includes sedatives, narcotics, antispasmodics, antibiotics, muscle relaxants, steroids, high blood pressure medicine, antacids, antidepressants, heart medicines, nonsteroidal anti-inflammatory medicines such as ibuprofen, and pain medicines.

  • Over-the-counter medicines. This includes allergy medicine, cough medicine, sleeping pills, and antinausea medicine. Diphenhydramine, found in many allergy and sleeping pills, is a very common cause.

  • Some herbal medicines

  • Psychoactive drugs

If you know someone at risk

Delirium is an emergency. If you think that your loved one has delirium, get medical help right away.


April 30, 2017


Inouye, SK, Delirium in elderly people, Lancet (2014); 282; 911-922

Reviewed By:  

Jasmin, Luc, MD,Turley, Ray, BSN, MSN