A concussion is a traumatic brain injury (TBI) that may result in a bad headache, altered levels of alertness, or unconsciousness.

It temporarily interferes with the way your brain works, and it can affect memory, judgment, reflexes, speech, balance, coordination, and sleep patterns.

See also: Concussion - first aid


A concussion may result when the head hits an object or a moving object strikes the head.

A concussion can result from a fall, sports activities, and car accidents. Significant movement of the brain (called jarring) in any direction can cause you to lose alertness (become unconscious). How long you remain unconscious may be a sign of the severity of the concussion.

However, concussions don't always involve a loss of consciousness. Most people who have a concussion never black out. You can have a concussion and not realize it.

ConcussionWatch this video about:Concussion


Symptoms of a concussion can range from mild to severe. They can include:

  • Altered level of consciousness (drowsy, hard to arouse, or similar changes)
  • Confusion, feeling spacey, or not thinking straight
  • Headache
  • Loss of consciousness
  • Memory loss (amnesia) of events before the injury or immediately after
  • Nausea and vomiting
  • Seeing flashing lights
  • Feeling like you have "lost time"

The following are emergency symptoms of a concussion. Seek immediate medical care if there are:

  • Changes in alertness and consciousness
  • Convulsions (seizures)
  • Muscle weakness on one or both sides
  • Persistent confusion
  • Persistent unconsciousness (coma)
  • Repeated vomiting
  • Unequal pupils
  • Unusual eye movements
  • Walking problems

Head injuries that result in concussion often are associated with injury to the neck and spine. Take particular care when moving patients who have had a head injury.

While recovering from a concussion, you may:

  • Be withdrawn, easily upset, or confused
  • Have a hard time with tasks that require remembering or concentrating
  • Have mild headaches
  • Be less tolerant of noise

Exams and Tests

The doctor will perform a physical exam and check your nervous system. There may be changes in your pupil size, thinking ability, coordination, and reflexes.

Tests that may be performed include:


A concussion with bleeding or brain damage must be treated in a hospital.

If the concussion occured during a sporting event and resulted in a headache, confusion, or change in alertness, a trained person must determine when that person can return to playing sports.

Children with concussion symptoms should avoid sports and from being overly active during recess, physical education classes, and other playtimes. Ask your doctor when your child can return to normal activities.

When your child can safely return to normal activities depends on the severity of the concussion. Some children may need to wait 1 to 3 months. Ask your child's doctor if it is okay before the child participates in any activity where there is a risk of hitting or injuring the head. Specifically, ask when your child can:

  • Play contact sports, such as football, hockey, and soccer
  • Ride a bicycle, motorcycle, or off-road vehicle
  • Driving a car (if they are old enough and licensed)
  • Ski, snowboard, skate, or participate in gymnastics or martial arts

Some organizations recommend that a child who had a concussion avoid sports activities that could produce a similar head injury for the rest of the season.

Treatment for a concussion may include:

  • Acetaminophen (Tylenol) for a headache. Do NOT use aspirin, ibuprofen (Motrin or Advil), naproxen, or similar drugs.
  • Eating a light diet.
  • Avoiding exercise, weight lifting, or heavy activities. Light activity around the home is okay. You do not need to stay in bed.
  • Avoiding alcohol until you have completely recovered.

An adult should stay with you for the first 12 - 24 hours after the concussion. Going to sleep is okay. However, someone should wake you up every 2 or 3 hours for the at least the first 12 hours. They can ask a simple question, such as your name, and then look for any changes in the way you look or act.

Outlook (Prognosis)

Healing or recovering from a concussion takes time. It may take days, weeks, or even months. You may be irritable, have trouble concentrating, be unable to remember things, have headaches, dizziness, and blurry vision. These problems will probably go away slowly. You may want to get help from family or friends before making important decisions.

Possible Complications

Complications from a concussion can include:

  • Bleeding in the brain (intracerebral hemorrhage)
  • Brain injury that results in physical, emotional, or intellectual changes

The second impact syndrome (SIS) is when a person gets a second concussion while still having symptoms from a first one. This raises the risk for brain swelling, which can be deadly.

When to Contact a Medical Professional

Call your health care provider if a head injury causes changes in alertness or produces any other worrisome symptoms.

If symptoms do not go away or are not improving after 2 or 3 weeks, talk to your doctor.

Call the doctor if the following symptoms occur:

  • Changes in behavior or unusual behavior
  • Changes in speech (slurred, difficult to understand, does not make sense)
  • Confusion
  • Difficulty waking up or becoming more sleepy
  • Double vision or blurred vision
  • Fever
  • Fluid or blood leaking from the nose or ears
  • Headache that is getting worse, lasts a long time, or does not get better with over-the-counter pain relievers
  • Problems walking or talking
  • Seizures
  • Vomiting more than three times


Attention to safety, including the use of appropriate athletic gear, such as bike helmets and seat belts, reduces the risk of head injury.


Ropper AH, Gorson KC. Clinical practice: concussion. N Engl J Med. 2007;356:166-172.

Hunt T, Asplund C. Concussion assessment and management. Clin Sports Med. 2009;5-17.

Update Date: 1/11/2012

Reviewed by: Jacob L. Heller, MD, MHA, Emergency Medicine, Virginia Mason Medical Center, Seattle, Washington. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.

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