CausesBy Mayo Clinic staff
Delirium occurs when the normal sending and receiving of signals in the brain becomes impaired. This impairment is most likely caused by a combination of factors that make the brain vulnerable and trigger a malfunction in brain activity.
Any condition that results in a hospital stay, especially in intensive care, increases the risk of delirium. Common causes include dehydration and infections, such as urinary tract infection, pneumonia, and skin and abdominal infections. Examples of other conditions that increase the risk of delirium include:
- Older age
- Fever and acute infection, particularly in children
- Previous delirium episodes
- Visual or hearing impairment
- Poor nutrition or dehydration
- Severe, chronic or terminal illness
- Multiple medical problems or procedures
- Treatment with multiple drugs
- Alcohol or drug abuse or withdrawal
A number of medications or combinations of medications can trigger delirium, including some types of:
- Pain medications
- Sleep medications
- Allergy medications (antihistamines)
- Medications for mood disorders, such as anxiety and depression
- Parkinson's disease medications
- Drugs for treating spasms or convulsions
- Asthma medications
Delirium may have more than one cause, such as a medical condition and medication toxicity.
- Delirium. In: Diagnostic and Statistical Manual of Mental Disorders DSM-IV-TR. 4th ed. Arlington, Va.: American Psychiatric Association; 2000. http://www.psychiatryonline.com. Accessed May 22, 2012.
- Dementia. In: Diagnostic and Statistical Manual of Mental Disorders DSM-IV-TR. 4th ed. Arlington, Va.: American Psychiatric Association; 2000. http://www.psychiatryonline.com. Accessed May 22, 2012.
- Ghandour A, et al. Detecting and treating delirium - key interventions you may be missing. The Journal of Family Practice. 2011;60:726.
- Martinez FT, et al. Preventing delirium in an acute hospital using a non-pharmacological intervention. Age and Aging. 2012;0:1.
- Francis J, et al. Diagnosis of delirium and confusional states. http://www.uptodate.com/index.html. Accessed May 24, 2012.
- Tips and resources for caregivers: Caring for yourself when you are caring for others. Ask Medicare: Information to help you care for others. http://www.medicare.gov/caregivers/caregiver-topics-support.html. Accessed May 24, 2012.
- Takahashi PY (expert opinion). Mayo Clinic, Rochester, Minn. June 28, 2012 & August 6, 2012.
- Philbrick KL (expert opinion). Mayo Clinic, Rochester, Minn. July 30, 2012.
- Sampson S (expert opinion). Mayo Clinic, Rochester, Minn. July 27, 2012.