Blow to the head or concussion

When you have a concussion or suffered a blow to the head it is important that you avoid being alone for the first 24 hours.

About your visit

You have hit your head, and there is a risk that you have or will have concussion. Symptoms of a concussion may appear up to 24 hours after you have hit your head.

When you get home

Avoid being alone for the first 24 hours

It is important that you are together with another adult for the first 24 hours. It is also important that they read this pamphlet.
They should keep an eye on you and make sure you are behaving as normal. They must wake you up 2-3 times during the night to check that you react as normal.

Expect headaches and other mild symptoms

It is normal to experience the following:

  • Headaches.
  • Nausea and vomiting.
  • Dizziness.
  • Trouble concentrating.
  • Fatigue.
  • Memory loss.

Dial 112 if you develop one or several of the following symptoms:

Dial 112 if:

  • you are hard to wake
  • you have severe vomiting
  • you experience cramps or have trouble controlling your arms and legs
  • you have double vision or experience other visual disorders
  • your speech becomes unintelligible
  • one pupil is larger than the other
  • you do not notice that others are speaking to you.

Dial 1813 for the medical helpline if your condition deteriorates

In very rare cases, you may begin to feel worse after arriving home. Dial 1813 immediately for the medical helpline if you develop one or several of the following symptoms:

  • Intense headache.
  • Increasing headache.
  • Increasing fatigue coupled with increased need to sleep.
  • Restlessness and strange behaviour.

Avoid mental exertion 

Do not do anything that requires concentration or other mental exertion for the first few days. Therefore, avoid:

  • vigorous physical activity, for example sports
  • screen time in front of a computer, cell phone or television
  • reading
  • work that requires high levels of concentration
  • very warm temperatures and sunbathing
  • direct sunlight
  • alcohol, drugs and parties (for at least three days).

Contact your general practitioner if your symptoms continue

Contact your general practitioner if you are still experiencing headaches, difficulty concentrating or other symptoms of a concussion after one or two weeks.

Worth knowing

Check your medical journal and test results

You can check your medical journal, health data and any test results at and They are both available as apps: MinSP and MinSundhed. Log on to the apps with your MitID.

We will notify your doctor

We will send information about your visit to the hospital to your general practitioner. Let us know if you do not want your general practitioner to receive information from the hospital.

Tell us about your experience

We would very much like to receive your feedback. If you are considering lodging a complaint, please contact the hospital’s impartial patient advisors. Read more here: (in Danish only).

Your personal data

The Capital Region of Denmark uses the personal data you share with us when you make an enquiry. You can read more about how we use your data and your rights on our website: (in Danish only).

Learn more

Learn more about head injuries and concussions at www.patienthå (in Danish only). Search under ’commotio cerebri’, ’hovedskade’ and ’hjernerystelse’.