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What is delirium? — Delirium is a brain disorder that causes people to be confused. People with delirium often have:
Trouble paying attention, or switching attention from one thing to another
Memory, language, or other thinking problems
Trouble knowing where they are, when it is, or who the people around them are
People with delirium are often very sleepy or hard to wake up. Or they can be overly active or upset. Sometimes, they see or hear things that aren't really there.
Symptoms of delirium can come and go over the course of a day, and often get worse toward the end of the day.
There are other terms that might come up when doctors talk about delirium. Doctors sometimes use the term "altered mental status" for when a person's brain isn't working normally. The word "confusion" means a person isn't thinking clearly.
What causes delirium? — Different kinds of conditions or situations can cause delirium. The most common reasons people have delirium are:
A medical condition, such as low blood sugar, pneumonia (infection of the lungs), or kidney failure
A side effect of medicines
Illegal drug use
Alcohol withdrawal – This is when people suddenly stop drinking after they have been drinking a lot of alcohol every day.
A problem in the brain, such as infection, seizure, or some types of strokes – Seizures are waves of abnormal electrical activity in the brain that can make people move or behave strangely. A stroke is when a part of the brain is damaged because of a problem with blood flow.
Delirium happens more often in people who:
Are older, have a lot of medical problems, or take a lot of medicines
Have another brain disorder, such as dementia – Dementia is a disorder that causes memory problems and makes it hard to think clearly.
Have vision or hearing problems
Delirium is most likely to happen when a person is in the hospital, especially if the person just had surgery or is in pain.
Should I call the doctor or nurse? — Yes. Many people who get delirium are already in a hospital. But if you are not in a hospital, it's important to call the doctor or nurse if you notice the symptoms listed above.
Will I need tests? — Yes. The doctor or nurse will do an exam and ask questions to check thinking and attention. He or she will do tests to find out what's causing the delirium. The tests will depend on the individual situation and can include:
Blood tests
Urine tests
A CT scan of the head – A CT scan is an imaging test that can create pictures of the brain.
A lumbar puncture (sometimes called a "spinal tap") – During this procedure, a doctor will put a thin needle into the lower back and take out a small amount of spinal fluid. Spinal fluid is the fluid that surrounds the brain and spinal cord. He or she will send the spinal fluid to a lab for tests.
An EEG (or "electroencephalogram") – An EEG is a test that measures electrical activity in the brain and records brain wave patterns (figure 1).
How is delirium treated? — Doctors treat delirium by treating the cause of the delirium, if it can be treated. For example, if a medicine is causing delirium, the doctor will stop or change that medicine. If an infection is causing delirium, he or she will treat the infection. Even with this treatment, delirium can last days to weeks, depending on what's causing it.
Doctors also treat delirium by helping a person's symptoms until the delirium gets better. Different ways doctors can do this include:
Making the person's hospital room as quiet as possible, especially at night
Giving the person medicine to help him or her sleep better at night
Having the hospital staff remind the person where he or she is, and why he or she is in the hospital
Giving the person medicine to help calm him or her down
Also, it often helps people with delirium to have family and other familiar people around them in the hospital.
Most people with delirium recover completely. But people who are older or have other brain problems, such as dementia, might not.
Can delirium be prevented? — Sometimes. Doctors try to lower the chances that a person in the hospital will get delirium by doing a few different things, like avoiding certain medicines. Other things doctors can do include making the person's room quiet so he or she can sleep, or giving the person eyeglasses or hearing aids in the daytime if they are used to using them.
If your family member is in the hospital, talk with his or her doctor or nurse about how to help prevent delirium.
All topics are updated as new evidence becomes available and our peer review process is complete.
This topic retrieved from UpToDate on: Mar 30, 2020.
Topic 16994 Version 7.0
Release: 28.2.2 - C28.105
© 2020 UpToDate, Inc. and/or its affiliates. All rights reserved.

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