A concussion is an injury to the brain caused by rapid, forceful movement of the brain against the skull. It is usually caused by a bump or blow to the head, but it can also occur when the upper body is shaken violently.
A concussion alters the way the brain functions. The effects can include headaches and problems with concentration, memory, balance, and coordination. These effects are usually temporary, but every concussion should be treated as a serious injury.
How common are concussions?
About 1.5 million Americans sustain a traumatic brain injury each year. Most traumatic brain injuries are concussions.
Who gets concussions?
Anyone can get a concussion, but risk factors include:
- Playing sports
- Being involved in a car crash or bicycle accident
- Being a soldier in combat
- Being physically abused
- Falling, especially in young children and older adults
- Having had a previous concussion
How is a concussion diagnosed?
Your doctor will review your symptoms and medical history, and conduct a neurological exam to evaluate:
Your doctor may do an imaging test if your symptoms are severe. A CT or MRI can show whether there is bleeding or swelling in your skull.
Symptoms of a concussion can show up immediately after a brain injury, or they may not appear or be noticed until hours or days later. Symptoms of a concussion include:
- Loss of consciousness (although most concussions occur without loss of consciousness)
- Appearance of being dazed or stunned
- Amnesia surrounding the traumatic event
- Nausea and vomiting
- Ringing in the ears
- Slurred speech
- Delayed response to questions
- Blurred or double vision
- Sensitivity to light or noise
- Personality changes
If you experience any of these symptoms or observe them in another person, contact a medical professional. Persistent or worsening symptoms could be a sign of a more severe brain injury and should be evaluated immediately in an emergency department.
Most people are able to fully recover from a concussion with physical and mental rest. Your doctor may tell you to avoid exercise and any activities that involve concentration.
If you experience another concussion before your previous injury has healed, it could lead to second impact syndrome. This is marked by swelling of the brain and can be fatal.
Acetaminophen (Tylenol) can help with headache pain. Other pain relievers, such as ibuprofen and aspirin, could increase the risk of bleeding.
- Date of last review: November 26, 2016
- Author: Javier Cárdenas, MD