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What is a concussion?

A concussion is a mild brain injury that can cause confusion, memory loss, and headache. Sometimes people pass out (lose consciousness) when they have a concussion, but not always.

A concussion can happen after a person has an injury to the head from getting hit, falling, or being in an accident.

What are the symptoms of a concussion?

Symptoms that can happen minutes to hours after a concussion include:

Memory loss – People sometimes forget what caused their injury, as well as what happened right before and after the injury.



Dizziness or trouble with balance

Nausea or vomiting

Feeling very tired

Acting cranky, irritable, or not like themselves

Symptoms that can happen hours to days after a concussion include:

Trouble walking or talking

Memory problems or problems paying attention

Trouble sleeping

Mood or behavior changes

Vision changes

Being bothered by noise or light

Will I need tests?

It depends on your injury and symptoms. To check if you have a concussion, your doctor will ask about your symptoms and do a physical exam. He or she will also ask you questions to check that you are thinking clearly.

If your doctor suspects a serious injury, he or she might order an imaging test of the brain, such as a CT or MRI scan. These tests create pictures of the skull and inside of the brain.

When should I call the doctor or nurse?

If you had a concussion, or think you might have had one, call your doctor or nurse. They can tell you whether you should go to the emergency department, and how quickly you should be seen.

After a concussion, your doctor might recommend that someone stay with you for 12 to 24 hours. This person should watch for any new symptoms.

You, or the person with you, should call the doctor or nurse if:

You vomit more than 3 times

You have a severe headache, or a headache that gets worse

You have a seizure

You have trouble walking or talking

Your vision changes

You feel weak or numb in part of your body

You lose control over your bladder or bowels

The person with you should also call right away if they have any trouble waking you up.

When can I play sports or do my usual activities again?

Ask your doctor when you can play sports or do your usual activities again. It will depend on your injury and symptoms, as well as the type of sport you play. Do not go back to playing on the same day as your injury.

It's important to let your brain heal completely after a concussion. Getting another concussion before your brain has healed may lead to serious brain problems.

How can I prevent another concussion?

To help prevent another concussion, you can:

Wear a helmet when you ride a bike or motorcycle, or play certain sports

Wear a seat belt when you drive or ride in a car

If you have one concussion, it's very important to try to prevent future concussions. Having many concussions might cause long-term brain damage and affect your thinking.

ReferenceThis topic retrieved from UpToDate on: Mar 12, 2020.

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