Confusion is the inability to think with your usual speed or clarity, including feeling disoriented and having difficulty paying attention, remembering, and making decisions.
Disorientation; Thinking - unclear; Thoughts - cloudy
Confusion may come on quickly or slowly over time, depending on the cause. Many times, confusion is temporary. Other times it is permanent and not curable. It may be associated with delirium or dementia.
Confusion is more common in the elderly, and often occurs during a hospital stay.
Some confused people may have strange or unusual behavior or may act aggressively.
Alcohol intoxication Brain tumor Concussion
Fluid and electrolyte imbalance
Head traumaor head injury
- Illness in an elderly person
- Illness in a person with existing neurological disease such as a stroke
- Lack of sleep (sleep deprivation)
Low blood sugar
- Low levels of oxygen (for example, from chronic lung disorders)
- Nutritional deficiencies, especially
niacin, thiamine, vitamin C, or vitamin B12 Seizures
- Sudden drop in body temperature (
Review Date: 02/06/2010
Reviewed By: David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine; Luc Jasmin, MD, PhD, Department of Neurosurgery at Cedars-Sinai Medical Center, Los Angeles, CA, and Department of Anatomy at UCSF, San Francisco, CA. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.