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What are common TBI symptoms?

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TBI symptoms vary depending on the extent of the injury and the area of the brain affected. Some symptoms appear immediately; others may appear several days or even weeks later. A person with TBI may or may not lose consciousness—loss of consciousness is not always a sign of severe TBI.

Symptoms of Mild TBI

A person with a mild TBI may experience:

  • Headache
  • Confusion
  • Lightheadedness
  • Dizziness
  • Blurred vision
  • Ringing in the ears
  • Tiredness or sleepiness
  • A bad taste in the mouth
  • A change in sleep habits
  • Behavior or mood changes
  • Trouble with memory, concentration, attention, or thinking
  • Loss of consciousness lasting a few seconds to minutes1
  • Sensitivity to light or sound
  • Nausea or vomiting2

Symptoms of Moderate or Severe TBI

A person with moderate or severe TBI may have some of the symptoms listed above. In addition, the person may experience any of the following:

  • Headache that gets worse or won’t go away
  • Repeated vomiting or nausea
  • Slurred speech
  • Convulsions or seizures
  • An inability to wake up from sleep
  • Enlargement of the pupil (dark center) of one or both eyes
  • Numbness or tingling of arms or legs
  • Loss of coordination
  • Increased confusion, restlessness, or agitation
  • Loss of consciousness lasting a few minutes to hours3

A person who suffers a blow to the head or another trauma that may have caused a TBI should seek medical attention.4


  1. National Institute of Neurological Disorders and Stroke. (2012). Traumatic brain injury information page. Retrieved May 24, 2012, from http://www.ninds.nih.gov/disorders/tbi/tbi.htm [top]
  2. Centers for Disease Control and Prevention. (2011). Concussion. Retrieved June 13, 2012, from http://www.cdc.gov/concussion/signs_symptoms.html [top]
  3. National Institute of Neurological Disorders and Stroke. (2012). Traumatic brain injury: Hope through research. Retrieved May 24, 2012, from http://www.ninds.nih.gov/disorders/tbi/detail_tbi.htm [top]
  4. American Academy of Family Physicians. Traumatic brain injury: Symptoms. Retrieved June 13, 2012, from http://familydoctor.org/familydoctor/en/diseases-conditions/traumatic-brain-injury/symptoms.html External Web Site Policy [top]

Last Reviewed: 05/21/2013
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