What is a concussion?

A concussion is a change in brain function caused by an injury to the head.

How does it occur?

A concussion occurs when a blow to the head causes shaking, jarring, stretching, swelling, or tearing of brain tissue and delicate nerve fibers.

What are the symptoms?

The symptoms of a concussion may include any or all of the following:

• headache

• dizziness

• confusion

• inability to concentrate

• nausea or vomiting

• not being able to remember events that happened just before the injury (amnesia)

• loss of consciousness

• seizures

• weakness

• sleepiness

• change in personality

• inappropriate speech or actions.

How is it diagnosed?

The diagnosis is based on the history of the injury and whether you had any symptoms of concussion after the injury.

Initially the severity of the concussion is assessed by the degree of amnesia after the injury and whether you lost consciousness and for how long.

The physical exam includes a complete evaluation of your nervous system. Your health care provider will test your strength, sensation, balance, reflexes, and memory. You will be tested again several times during the next hour to detect any worsening of brain function, which might occur if you have any bleeding (hemorrhage) or swelling in the brain.

Skull x-rays are not routinely done because they do not provide information about the condition of the brain. However, if your concussion was severe (for example, you lost consciousness for more than 5 minutes), your health care provider may choose to do a computed tomography (CT) scan of the brain. This special type of x-ray can show bleeding in the brain or on its surface. CT scans are not necessary with most concussions.

Neck x-rays may be done to rule out injury to the spine, depending on how the head injury occurred.

How is it treated?

Treatment consists mainly of observation and rest. After you leave the medical office, you need to be observed by your family or friends at home for the next 8 to 12 hours. When you are sleeping, someone should wake you up and check you every 2 to 4 hours. Symptoms to report to the health care provider include:

• confusion

• seizures

• unequal pupil size

• restlessness or irritability

• trouble using your legs or arms

• repeated vomiting

• headache that will not go away after being treated with acetaminophen (Tylenol)

• stiff neck

• garbled speech

• bleeding from the ears or nose

• decreasing alertness

• unusual sleepiness.

If you are stable and recovering during the next 24 hours, you should rest for an additional day or two. As your symptoms go away, you can begin to go back to your usual daily routine. However, you should stay away from any activities that would risk reinjury. A second concussion before the first one has healed could be very serious. Your doctor will tell you when it is safe to return to sports and other activities.

How long will the effects last?

You may have the symptoms of a concussion for several days after the injury.

What can I do to prevent concussions?

Using proper equipment (such as helmets and seat belts) and following proper techniques in sports such as football and soccer are the best ways to prevent concussions. But when accidents do happen, remember that concussions can be severe. It's especially important to understand that receiving a second blow to the head before the first injury is fully healed can be fatal, even if the second injury seems minor.