What Is a Concussion?

A concussion is a type of mild traumatic brain injury (or mild TBI). It happens when a blow to the head or an injury makes the head move back and forth with a lot of force. This causes chemical changes in the brain and, sometimes, damage to the brain cells. 

Teens who follow their health care provider's recommendations usually feel better within a few weeks of the concussion.

What Are the Signs & Symptoms of a Concussion?

Someone with a concussion might be knocked out (this is called a loss of consciousness). But a person doesn't have to get knocked out to have a concussion.

Signs and symptoms of a concussion include:

  • headache
  • blurred or double vision
  • dizziness, balance problems, or trouble walking
  • confusion and saying things that don't make sense
  • being slow to answer questions
  • slurred speech
  • nausea or vomiting
  • not remembering what happened
  • not feeling well

Symptoms of a concussion usually happen right away, but can show up hours or days after an injury. A teen with a concussion may:

  • have trouble focusing
  • have learning or memory problems
  • have a headache that gets worse
  • have sleep problems
  • feel sad, easily upset or angered, or nervous 

If you have been diagnosed with a concussion, call your health care provider right away or have someone take you to the ER if you:

  • have a severe headache or one that gets worse
  • have a seizure
  • pass out
  • have other symptoms (such as continued vomiting) that worry you

These could be signs of a serious concussion, and you might need treatment in a hospital.

What Happens in a Concussion?

The skull helps protect the brain from injury. Spinal fluid cushions the brain inside the skull. A blow or jolt to the head can hurt the brain directly or make the brain move around and bang up against the hard bone of the skull. This changes the signals between nerves, which causes concussion symptoms.

How Do Teens Get Concussions?

Most concussions in teens happen while playing sports. The risk is highest for those who play football, ice hockey, lacrosse, soccer, and field hockey.

Concussions can also happen from:

  • car or bicycle accidents
  • a fight
  • a fall

How Are Concussions Diagnosed?

To diagnose a concussion, the health care provider will:

  • ask about how and when the head injury happened
  • ask about symptoms
  • test memory and concentration
  • do an exam and test balance, coordination, and reflexes

If a head injury happens while someone is playing sports, a coach or athletic trainer may do sideline concussion testing. This is when a trained person does a few simple tests after a head injury to help decide if the athlete needs immediate medical care. An athlete who has a head injury must stop playing and see a doctor before returning to play.

Many schools or sports leagues are using baseline concussion tests. Baseline testing uses computer programs to test a player's normal brain function. It checks attention, memory, and speed of thinking. Doctors compare testing after an injury with baseline results to see how someone is recovering.

Concussions do not show up on a CAT scan or MRI. So, the doctor may not order a brain scan for a mild concussion. A CAT scan or MRI might be done to look for other problems if someone:

  • was knocked out
  • keeps vomiting
  • has a severe headache or a headache that gets worse
  • was injured in serious accident, such as from a car accident or very high fall

How Are Mild Concussions Treated?

Each person with a concussion heals at their own pace. It's important to find a balance between doing too much and too little.

At first, you need to cut back on physical activities and those that require a lot of concentration. Then, you can start trying these activities again. Your symptoms don't have to be completely gone for you to add activities. But if symptoms interfere with an activity, take a break from it. You can try it again after a few minutes, or you can try a less strenuous version of the activity.

Rest (for 1–2 days after the concussion)

  • Relax at home. You can do calm activities, such as talking to family and friends, reading, drawing, or playing a quiet game. If symptoms interfere with an activity, take a break from it. You can try it again after a few minutes or longer, or you can try a less strenuous version of the activity. 
  • Avoid or cut down on screen time. Video games, texting, watching TV, and using social media are likely to cause symptoms or make them worse.
  • Don't drive. 
  • Avoid all sports and any activities (such as roughhousing with friends, or riding a bike or skateboard) that could lead to another head injury. 
  • Sleep:
    • Get plenty of sleep (at least 8–10 hours in a 24-hour period).
    • Keep regular sleep and wake times.
    • No screen time or listening to loud music before bed.
    • Avoid caffeine.
    • Nap during the day, as needed.
  • For the first few days after the injury, if you have a headache and your health care provider says it's OK, you can take acetaminophen (Tylenol® or a store brand) or ibuprofen (Advil®, Motrin® or a store brand).

Light Activity (usually within a few days to a week after the concussion)

  • Slowly try more activities, such as going for a walk or watching TV. If symptoms interfere with an activity, take a break from it. You can try it again after a few minutes or longer, or you can try a less strenuous version of the activity.
  • After a few days, you should feel well enough to return to school. Work with your health care provider and a school team to create a plan for returning to school. You may need to start with a shorter day or a lighter workload. If you're not back in school by 5 days after the concussion, call your health care provider.
  • Ask your health care provider when you can drive again.
  • Keep avoiding all sports and any activities that could lead to another head injury.
  • Keep getting plenty of sleep. If you don't feel tired during the day, you don't need to nap.
  • If you still need medicine for headaches, talk to your health care provider.

Moderate Activity (usually about a week after the concussion)

  • If your symptoms are nearly gone, you can go back to most activities, including regular schedules for school and work.
  • Keep avoiding all sports and any activities that could lead to another head injury.
  • If symptoms interfere with an activity, take a break from it. You can try it again after a few minutes or longer, or you can try a less strenuous version of the activity

Regular Activity (usually within a month of the concussion)

  • If you no longer have any concussion symptoms, you can go back to all other activities, except sports, that you used to do.
  • For sports, your health care provider will work with your coach and athletic trainer (if available) to create a clear, written plan for a gradual return to play. Don't go back to playing sports until your health care provider says it's OK.

When Can Teens Go Back to Sports After a Concussion?

Student athletes must wait until their health care provider says it's safe before returning to sports. This means that they:

  • have had a physical exam
  • are back in school
  • have no symptoms
  • aren't taking any medicines for concussion symptoms
  • are back to their baseline results on physical and cognitive testing

Hurrying back to sports and other physical activities puts teens at risk for second-impact syndrome. This is when someone gets another head injury before the concussion has healed. Although very rare, second-impact syndrome can cause lasting brain damage and even death. Almost every state has rules about when teens with concussions can start playing sports again.

Looking Ahead

People are much more likely to get a concussion if they've had one before. So preventing concussions is very important after a head injury. To prevent another concussion:

  • Be sure that any teams you are on have rules to reduce the risk of concussions, such as limits on tackling (football) or heading the ball (soccer).
  • Be sure to wear a helmet when skiing, snowboarding, biking, riding a scooter, skateboarding, or rollerblading. A concussion still can happen while you wear a helmet, but the helmet can protect you from a skull fracture and serious brain injury.
  • If you do get another head injury, never ignore symptoms or try to "tough it out." Stop the sport or activity that you are doing and get medical care right away.
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Note: All information is for educational purposes only. For specific medical advice, diagnoses, and treatment, consult your doctor. © 1995-2021 KidsHealth®. All rights reserved. Images provided by The Nemours Foundation, iStock, Getty Images, Veer, Shutterstock, and Clipart.com.