Delirium (PDQ®): Supportive care - Patient Information [NCI]

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General Information About Delirium

Delirium is a confused mental state that can occur in patients who have cancer.

Delirium is a confused mental state that can occur in patients who have cancer, especially advanced cancer. Patients with delirium have problems with the following:

  • Attention.
  • Thinking.
  • Awareness.
  • Behavior.
  • Emotions.
  • Judgement.
  • Memory.
  • Muscle control.
  • Sleeping and waking.

There are three types of delirium:

  • Hypoactive: The patient is not active and seems sleepy, tired, or depressed.
  • Hyperactive: The patient is restless or agitated.
  • Mixed: The patient changes back and forth between being hypoactive and hyperactive.

Delirium may come and go during the day.

The symptoms of delirium usually occur suddenly. They often occur within hours or days and may come and go. Delirium is often temporary and can be treated. However, in the last 24 to 48 hours of life, delirium may be permanent because of problems like organ failure. Most advanced cancer patients have delirium that occurs in the last hours to days before death.

This summary is about delirium in adults.

Causes of Delirium

Delirium may be caused by cancer, cancer treatment, or other medical conditions.

There is often more than one cause of delirium in a cancer patient, especially when the cancer is advanced and the patient has many medical conditions. Causes of delirium include the following:

  • Organ failure, such as liver or kidney failure.
  • Electrolyte imbalances: Electrolytes are important minerals (including salt, potassium, calcium, and phosphorous) in blood and body fluids. These electrolytes are needed to keep the heart, kidneys, nerves, and muscles working the way they should.
  • Infections.
  • Paraneoplastic syndromes: Symptoms that occur when cancer-fighting antibodies or white blood cells attack normal cells in the nervous system by mistake.
  • Side effects of medicines and treatments: Patients with cancer may take medicines with side effects that include delirium and confusion. The effects usually go away after the medicine is stopped.
  • Withdrawal from medicines that depress (slow down) the central nervous system (brain and spinal cord).

It is important to know the risk factors for delirium.

Patients with cancer are likely to have more than one risk factor for delirium. Identifying risk factors early may help prevent delirium or decrease the time it takes to treat it. Risk factors include the following:

  • Serious illness.
  • Having more than one disease.
  • Older age.
  • Dementia.
  • Low level of albumin (protein) in the blood, which is often caused by liver problems.
  • Infection.
  • High level of nitrogen waste products in the blood, which is often caused by kidney problems.
  • Taking medicines that affect the mind or behavior.
  • Taking high doses of pain medicines, such as opioids.

The risk increases when the patient has more than one risk factor. Older patients with advanced cancer who are hospitalized often have more than one risk factor for delirium.

Effects of Delirium on the Patient, Family, and Health Care Providers

Delirium causes changes in the patient that can upset the family and caregivers.

Delirium may be dangerous to the patient if his or her judgment is affected. Delirium can cause the patient to behave in unusual ways. Even a quiet or calm patient can have a sudden change in mood or become agitated and need more care.

Delirium can be upsetting to the family and caregivers. When the patient becomes agitated, family members often think the patient is in pain, but this may not be the case. Learning about differences between the symptoms of delirium and pain may help the family and caregivers understand how much pain medicine is needed. Health care providers can help the family and caregivers learn about these differences.

Delirium may affect physical health and communication.

Patients with delirium are:

  • More likely to fall.
  • Sometimes unable to control bladder and/or bowels.
  • More likely to become dehydrated (drink too little water to stay healthy).

They often need a longer hospital stay than patients without delirium.

The confused mental state of these patients may make them:

  • Unable to talk with family members and caregivers about their needs and feelings.
  • Unable to make decisions about care.

This makes it harder for health care providers to assess the patient's symptoms. The family may need to make decisions for the patient.

Diagnosing Delirium

Possible signs of delirium include sudden personality changes, problems thinking, and unusual anxiety or depression.

When the following symptoms occur suddenly, they may be signs of delirium:

  • Agitation.
  • Not cooperating.
  • Changes in personality or behavior.
  • Problems thinking.
  • Problems paying attention.
  • Unusual anxiety or depression.

The symptoms of delirium are a lot like symptoms of depression and dementia.

Early symptoms of delirium are like symptoms of depression and dementia. Delirium that causes the patient to be inactive may appear to be depression. Delirium and dementia both cause problems with memory, thinking, and judgment. Dementia may be caused by a number of medical conditions, including Alzheimer disease. Differences in the symptoms of delirium and dementia include the following:

  • Patients with delirium often show changes in how alert or aware they are. Patients who have dementia usually stay alert and aware until the dementia becomes very advanced.
  • Delirium occurs suddenly (within hours or days). Dementia appears gradually (over months to years) and gets worse over time.

Older patients with cancer may have both dementia and delirium. This can make it hard for the doctor to diagnose the problem. If treatment for delirium is given and the symptoms continue, then the diagnosis is more likely dementia. Checking the patient's health and symptoms over time can help diagnose delirium and dementia.

Physical exams and other laboratory tests are used to diagnose the causes of delirium.

Doctors will try to find the causes of delirium.

  • Physical exam and history: An exam of the body to check general signs of health, including checking for signs of disease, such as lumps or anything else that seems unusual. A history of the patient's health habits, past illnesses including depression, and treatments will also be taken. A physical exam can help rule out a physical condition that may be causing symptoms.
  • Laboratory tests: Medical procedures that test samples of tissue, blood, urine, or other substances in the body. These tests help to diagnose disease, plan and check treatment, or monitor the disease over time.

Treatment of Delirium

Treatment includes looking at the causes and symptoms of delirium.

Both the causes and the symptoms of delirium may be treated. Treatment depends on the following:

  • Where the patient is living, such as home, hospital, or nursing home.
  • How advanced the cancer is.
  • How the delirium symptoms are affecting the patient.
  • The wishes of the patient and family.

Treating the causes of delirium usually includes the following:

  • Stopping or lowering the dose of medicines that cause delirium.
  • Giving fluids to treat dehydration.
  • Giving drugs to treat hypercalcemia (too much calcium in the blood).
  • Giving antibiotics for infections.

In a terminally ill patient with delirium, the doctor may treat just the symptoms. The doctor will continue to watch the patient closely during treatment.

Treatment without medicines can also help relieve symptoms.

Controlling the patient's surroundings may help with mild symptoms of delirium. The following may help:

  • Keep the patient's room quiet and well-lit, and put familiar objects in it.
  • Put a clock or calendar where the patient can see it.
  • Have family members around.
  • Keep the same caregivers as much as possible.

Patients who may hurt themselves or others may need to have physical restraints.

Treatment may include medicines.

Medicines may be used to treat the symptoms of delirium depending on the patient's condition and heart health. These medicines have serious side effects and the patient will be watched closely by a doctor. These medicines include the following:

  • Haloperidol.
  • Olanzapine.
  • Risperidone.
  • Lorazepam.
  • Midazolam.

Sedation may be used for delirium at the end of life or when delirium does not get better with treatment.

When the symptoms of delirium are not relieved with standard treatments and the patient is near death, in pain, or has trouble breathing, other treatment may be needed. Sometimes medicines that will sedate (calm) the patient will be used. The family and the health care team will make this decision together.

The decision to use sedation for delirium may be guided by the following:

  • The patient will have repeated assessments by experts before the delirium is considered to be refractory (doesn't respond to treatment).
  • The decision to sedate the patient is reviewed by a team of health care professionals and not made by one doctor.
  • Temporary sedation, for short periods of time such as overnight, is considered before continuous sedation is used.
  • The team of health care professionals will work with the family to make sure the team understands the family's views and that the family understands palliative sedation.

Current Clinical Trials

Use our clinical trial search to find NCI-supported cancer clinical trials that are accepting patients. You can search for trials based on the type of cancer, the age of the patient, and where the trials are being done. General information about clinical trials is also available.

About This PDQ Summary

About PDQ

Physician Data Query (PDQ) is the National Cancer Institute's (NCI's) comprehensive cancer information database. The PDQ database contains summaries of the latest published information on cancer prevention, detection, genetics, treatment, supportive care, and complementary and alternative medicine. Most summaries come in two versions. The health professional versions have detailed information written in technical language. The patient versions are written in easy-to-understand, nontechnical language. Both versions have cancer information that is accurate and up to date and most versions are also available in Spanish.

PDQ is a service of the NCI. The NCI is part of the National Institutes of Health (NIH). NIH is the federal government's center of biomedical research. The PDQ summaries are based on an independent review of the medical literature. They are not policy statements of the NCI or the NIH.

Purpose of This Summary

This PDQ cancer information summary has current information about the causes and treatment of delirium. It is meant to inform and help patients, families, and caregivers. It does not give formal guidelines or recommendations for making decisions about health care.

Reviewers and Updates

Editorial Boards write the PDQ cancer information summaries and keep them up to date. These Boards are made up of experts in cancer treatment and other specialties related to cancer. The summaries are reviewed regularly and changes are made when there is new information. The date on each summary ("Updated") is the date of the most recent change.

The information in this patient summary was taken from the health professional version, which is reviewed regularly and updated as needed, by the PDQ Supportive and Palliative Care Editorial Board.

Clinical Trial Information

A clinical trial is a study to answer a scientific question, such as whether one treatment is better than another. Trials are based on past studies and what has been learned in the laboratory. Each trial answers certain scientific questions in order to find new and better ways to help cancer patients. During treatment clinical trials, information is collected about the effects of a new treatment and how well it works. If a clinical trial shows that a new treatment is better than one currently being used, the new treatment may become "standard." Patients may want to think about taking part in a clinical trial. Some clinical trials are open only to patients who have not started treatment.

Clinical trials can be found online at NCI's website. For more information, call the Cancer Information Service (CIS), NCI's contact center, at 1-800-4-CANCER (1-800-422-6237).

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The best way to cite this PDQ summary is:

PDQ® Supportive and Palliative Care Editorial Board. PDQ Delirium. Bethesda, MD: National Cancer Institute. Updated <MM/DD/YYYY>. Available at: Accessed <MM/DD/YYYY>. [PMID: 26389165]

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Last Revised: 2019-04-26

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