Epilepsy: People who have had a concussion double their risk of develping epilepsy within the first five years after the injury.
Cumulative effects of multiple brain injuries: Evidence exists indicating that people who have had multiple concussive brain injuries over the course of their lives may acquire lasting, and even progressive, conqnitive impairment that limits functional ability.
Second impact syndrome: Sometimes, experiencing a second concussion before signs and symptoms of a first concussion have resolved may result in rapid and typically fatal brain swelling. After a concussion, the levels of brain chemicals are altered. It usually takes about a week for these levels to stabilize again. However, the time it takes to recover from a concussion is variable, and it is important for athletes never to return to a sport while theyre still experiancing signs and symptoms of a concussion.