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Delirium: Cancer Treatment Side Effect

An older patient and family member meet with his doctor to get advice about delirium and confusion.

Talk with your loved one’s doctor to identify the causes of delirium and the best way to treat or manage it.

Credit: National Cancer Institute

What is delirium?

Delirium is a confused mental state that includes changes in awareness, thinking, judgment, sleeping patterns, as well as behavior. Although delirium can happen at the end of life, many episodes of delirium are caused by medicine or dehydration and are reversible.

The symptoms of delirium usually occur suddenly (within hours or days) over a short period of time and may come and go. Although delirium may be mistaken for depression or dementia, these conditions are different and have different treatments.

Different types of delirium and symptoms

The three main types of delirium include:

  • Hypoactive delirium: The patient seems sleepy, tired, or depressed.
  • Hyperactive delirium: The patient is restless, anxious, or suddenly agitated and uncooperative.
  • Mixed delirium: The patient changes back and forth between hypoactive delirium and hyperactive delirium.

Causes of delirium

Your health care team will work to find out what is causing delirium, so that it can be treated. Causes of delirium may include:

Early monitoring of someone with these risk factors for delirium may prevent it or allow it to be treated more quickly.

Changes caused by delirium can be upsetting for family members and dangerous to the person with cancer, especially if judgment is affected. People with delirium may be more likely to fall, unable to control their bladder and/or bowels, and more likely to become dehydrated. Their confused state may make it difficult to talk with others about their needs and make decisions about care. Family members may need to be more involved in decision-making.

Ways to treat delirium in people with cancer

Steps that can be taken to treat symptoms related to delirium include:

  • Treat the causes of delirium: If medicines are causing delirium, then reducing the dose or stopping them may treat delirium. If conditions such as dehydration, poor nutrition, and infections are causing the delirium, then treating these may help.
  • Control surroundings: If the symptoms of delirium are mild, it may help to keep the room quiet and well lit, with a clock or calendar and familiar possessions. Having family members around and keeping the same caregivers, as much as possible, may also help.
  • Consider medicines: Medicines are sometimes given to treat the symptoms of delirium. However, these medicines have serious side effects and patients receiving them require careful observation by a doctor.
  • Sometimes sedation may help: After discussion with family members, sedation is sometimes used for delirium at the end of life, if it does not get better with other treatments. The doctor will discuss the decisions involved in using sedation to treat delirium with the family.

Talking with your family member's health care team

Prepare for the visit by making a list of questions to ask. Consider adding these questions to your list:

  • Is my family member at risk for delirium?
  • What is causing the delirium?
  • What problems should we call you about?
  • What treatments are advised for my family member?