Diseases & Conditions

Acute Delirium - Delirium

Overview, Causes, & Risk Factors

Delirium can be caused by many medical conditions. It describes the confused state of mind in a person. With delirium, the person may be unable to maintain attention, and thinking may be disorganized. The brain is unable to process information in the proper way.

What is going on in the body?

A person with delirium is unable to focus attention or reply correctly to questions. Delirium usually comes on quickly and needs to be assessed and treated right away. It can usually be turned around once the cause is known. Delirium is more common in older people and may uncover dementia that wasn't noticed before.

What are the causes and risks of the condition?

Delirium can be caused by many things including:

  • abnormal sodium, chloride, ammonia, or other electrolyte levels in the blood
  • alcohol or drugs
  • head injury
  • liver or kidney failure, such as acute renal failure
  • low blood glucose
  • low oxygen levels in the blood
  • poisonings
  • seizures
  • severe dehydration
  • severe infections, such as a blood infection known as sepsis
  • withdrawal from drugs or alcohol

  • Symptoms & Signs

    What are the signs and symptoms of the condition?

    A person who is delirious:

  • cannot stay focused on what is going on around him or her
  • may be confused about time, place, or people
  • may be unable to identify friends or family
  • may have scattered and flawed thinking
  • may ramble or use garbled speech
  • The person could have:

  • hallucinations
  • memory impairment
  • a reduced level of consciousness
  • sleep problems

  • Diagnosis & Tests

    How is the condition diagnosed?

    Delirium requires immediate medical attention. A complete medical history and physical exam is necessary. Lab tests include drug and alcohol screening, blood glucose, and electrolytes, among others. A spinal tap or a cranial CT scan is often needed.

    Prevention & Expectations

    What can be done to prevent the condition?

    The best way to prevent delirium is to avoid illegal drugs and overuse of alcohol. It is important to seek proper treatment for all medical conditions. People with diabetes must monitor their blood glucose often to prevent very low or high levels. An attempt to eat healthy and stay healthy is important.

    What are the long-term effects of the condition?

    People with delirium may require a long stay in the hospital. If the cause cannot be established or treated, they may have a poor outcome.

    What are the risks to others?

    People who are delirious can become very upset and even violent. Caregivers may be injured by accident.

    Treatment & Monitoring

    What are the treatments for the condition?

    Treatment depends on the cause of the delirium. Symptoms can usually be reversed once the actual cause is named and treated. This is particularly true if the cause is low blood sugar or hypoglycemia. People with delirium are most comfortable in an environment that is:

  • quiet
  • calm
  • low-lit
  • familiar
  • Restraints may be necessary if the person is highly agitated. Sometimes the agitation must also be treated with medicine. In this case, the smallest dose of medicine is used because the drugs themselves may worsen the confusion at the same time that they calm the agitation. Medicines are stopped as soon as possible so recovery from delirium can be assessed.

    What are the side effects of the treatments?

    Some psychoactive medicines can actually cause confusion, which is a symptom of delirium. Usually, few major side effects appear from treatment after the cause of delirium is identified.

    What happens after treatment for the condition?

    Recovery from delirium can be slow. The rate of recovery can depend on the cause. Elderly people often recover at a slower rate.

    How is the condition monitored?

    The individual is monitored through blood chemistry studies and through physical exams. The specific monitoring will differ based on the cause of the delirium.


    Author:Terry Mason, MPH
    Date Written:
    Editor:Crist, Gayle P., MS, BA
    Edit Date:06/13/02
    Reviewer:Vincent J. Toups, MD
    Date Reviewed:05/07/01


    Merck Manual, Whitehouse Station, New Jersey, 1995-2000

    On-line medical dictionary, 2000

    Mayo Clinic, Geriatric Medicine, Topics in Geriatrics, Mayo Foundation for Medical Education and Research, 1996-2000

    Taber's Cyclopedic Medical Dictionary, F.A. Davis Company, Philidelphia, PA