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Describe concussion: What Is a Concussion? | HEADS UP

Concussion: MedlinePlus Medical Encyclopedia

A concussion may occur when the head hits an object, or a moving object strikes the head. A concussion is a less severe type of brain injury. It may also be called a traumatic brain injury.

A concussion can affect how the brain works. The amount of brain injury and how long it will last depends on how severe the concussion is. A concussion may lead to headaches, changes in alertness, loss of consciousness, memory loss, and changes in thinking.

A concussion can result from a fall, sports activities, vehicular accidents, assault, or other direct injury to the skull. A big movement of the brain (called jarring) in any direction can cause a person to lose alertness (become unconscious). How long the person stays unconscious may be a sign of how bad the concussion is.

Concussions do not always lead to loss of consciousness. Most people never pass out. They may describe seeing all white, all black, or stars. A person can also have a concussion and not realize it.

Watch this video about:Concussion

Symptoms of a milder concussion can include:

  • Acting somewhat confused, feeling unable to concentrate, or not thinking clearly
  • Being drowsy, hard to wake up, or similar changes
  • Headache
  • Loss of consciousness for a fairly short period of time
  • Memory loss (amnesia) of events before the injury or right after
  • Nausea and vomiting
  • Seeing flashing lights, light sensitivity
  • Feeling like you have “lost time”
  • Sleep abnormalities

The following are emergency symptoms of a more severe head injury or concussion. Seek medical care right away if there are:

  • Changes in alertness and consciousness
  • Confusion that does not go away
  • Seizures
  • Muscle weakness on one or both sides of the body
  • Pupils of the eyes that are not equal in size
  • Symptoms in just one eye
  • Unusual eye movements
  • Repeated vomiting
  • Walking or balance problems
  • Unconsciousness for a longer period of time or that continues (coma)

Head injuries that cause a concussion often occur with injury to the neck and spine. Take special care when moving people who have had a head injury.

The health care provider will perform a physical exam. The person’s nervous system will be checked. There may be changes in the person’s pupil size, thinking ability, coordination, and reflexes.

Tests that may be done include:

  • Blood and urine tests
  • EEG (brain wave test) may be needed if seizures continue
  • Head CT (computerized tomography) scan
  • MRI of the brain (magnetic resonance imaging) of the brain
  • X-rays

For a mild head injury, no treatment may be needed. But be aware that the symptoms of a head injury can show up later.

Your providers will explain what to expect, how to manage any headaches, how to treat your other symptoms, when to return to sports, school, work, and other activities, and signs or symptoms to worry about.

  • Children will need to be watched and make activity changes.
  • Adults also need close observation and activity changes.

Both adults and children must follow the provider’s instructions about when it will be possible to return to sports.

You will likely need to stay in the hospital if:

  • Emergency or more severe symptoms of head injury are present
  • There is a skull fracture
  • There is any bleeding under your skull or in the brain

Healing or recovering from a concussion takes time. It may take days to weeks, or even months. During that time you may:

  • Be withdrawn, easily upset, or confused, or have other mood changes
  • Have a hard time with tasks that require memory or concentration
  • Have mild headaches
  • Be less tolerant of noise
  • Be very tired
  • Feel dizzy
  • Have blurry vision at times

These problems will probably recover slowly. You may want to get help from family or friends for making important decisions.

In a small number of people, symptoms of the concussion do not go away. The risk for these long-term changes in the brain is higher after more than one concussion.

Seizures may occur after more severe head injuries. You or your child may need to take anti-seizure medicines for a period of time.

More severe traumatic brain injuries may result in many brain and nervous system problems.

Contact the provider if:

  • A head injury causes changes in alertness.
  • A person has other worrisome symptoms.
  • Symptoms do not go away or are not improving after 2 or 3 weeks.

Contact the provider right away if the following symptoms occur:

  • Increased sleepiness or difficulty waking up
  • Stiff neck
  • Changes in behavior or unusual behavior
  • Changes in speech (slurred, difficult to understand, does not make sense)
  • Confusion or problems thinking straight
  • Double vision or blurred vision
  • Fever
  • Fluid or blood leaking from the nose or ears
  • Headache that is getting worse, lasts a long time, or does not get better with over-the-counter pain relievers
  • Problems walking or talking
  • Seizures (jerking of the arms or legs without control)
  • Vomiting more than 3 times

If symptoms do not go away or are not improving a lot after 2 or 3 weeks, talk to your provider.

Not all head injuries can be prevented. Increase safety for you and your child by following these steps:

  • Always use safety equipment during activities that could cause a head injury. These include seat belts, bicycle or motorcycle helmets, and hard hats.
  • Learn and follow bicycle safety recommendations.

Do not drink and drive. Do not allow yourself to be driven by someone who may have been drinking alcohol or is otherwise impaired.

Brain injury – concussion; Traumatic brain injury – concussion; Closed head injury – concussion

  • Concussion in adults – discharge
  • Concussion in adults – what to ask your doctor
  • Concussion in children – discharge
  • Concussion in children – what to ask your doctor
  • Preventing head injuries in children
  • Brain
  • Concussion

Liebig CW, Congeni JA. Sports-related traumatic brain injury (concussion). In: Kliegman RM, St Geme JW, Blum NJ, Shah SS, Tasker RC, Wilson KM, eds. Nelson Textbook of Pediatrics. 21st ed. Philadelphia, PA: Elsevier; 2020:chap 708.

McClincy MP, Olgun ZD, Dede O. Orthopedics. In: Zitelli, BJ, McIntire SC, Nowalk AJ, Garrison J, eds. Zitelli and Davis’ Atlas of Pediatric Physical Diagnosis. 8th ed. Philadelphia, PA: Elsevier; 2023:chap 22.

Papa L, Goldberg SA. Head trauma. In: Walls RM, Hockberger RS, Gausche-Hill M, eds. Rosen’s Emergency Medicine: Concepts and Clinical Practice. 10th ed. Philadelphia, PA: Elsevier; 2023:chap 33.

Trofa DP, Caldwell J-M E, Li XJ. Concussion and brain injury. In: Miller MD, Thompson SR, eds. DeLee, Drez, & Miller’s Orthopaedic Sports Medicine. 5th ed. Philadelphia, PA: Elsevier; 2020:chap 126.

Updated by: Jesse Borke, MD, CPE, FAAEM, FACEP, Attending Physician at Kaiser Permanente, Orange County, CA. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team. Editorial update 04/11/2023.

Concussion – symptoms, signs and treatment

If someone is confused or unconscious after an injury to the head, call triple zero (000) and ask for an ambulance.

Key facts

  • Concussion is a mild brain injury caused by a knock or blow to the head or a sudden change in motion.
  • Concussions are common in contact sports such as football and boxing.
  • Common symptoms of concussion are confusion, memory loss, headache, vomiting and vision or speech problems.
  • If you think someone has had a concussion while playing sport, they should not return to play that day, even if they feel well.
  • The main treatment for concussion is rest, followed by a gradual return to physical and mental activity.

What is concussion?

Concussion is a minor traumatic brain injury usually caused by a blow to the head. Most people who have concussion will recover on their own within 2 weeks, but complications can occur. It is important that people with concussion rest and that their recovery is monitored with follow-up visits to a health professional.

What are the signs and symptoms of concussion?

The most common symptoms of concussion are confusion and/or memory loss about the event that led to the head injury.

Other common early symptoms of concussion include:

  • headache
  • dizziness
  • vertigo
  • nausea and/or vomiting
  • lack of awareness of your surroundings
  • vision and speech difficulties

Concussion does not always cause a person to become unconscious.

More subtle signs of concussion may include:

  • difficulty concentrating
  • sensitivity to noise or light
  • behavioural or emotional changes
  • feeling dazed
  • fatigue

CHECK YOUR SYMPTOMS — Use the Symptom Checker and find out if you need to seek medical help.

What causes concussion?

Concussion happens when the brain hits the inside of the skull. A concussion can be caused by many things, for example, a blow to the head or a car accident. Concussion can also result from a sudden change in motion. This is why concussion is a common sporting injury, especially in contact sports, such as boxing, Australian rules football, rugby league and rugby. Activities with a high risk of falls, such as horse riding, cycling and skiing, are also common causes of concussion.

What should I do if I think someone has concussion?

If someone is confused or unconscious after an injury to the head, call triple zero (000) and ask for an ambulance.

  • If you think someone has concussion after a head injury, follow the steps of basic first aid (DRABCD).
  • If you suspect that the person has an injury to their neck or back, do not move them, and call an ambulance immediately. If you do not suspect a spinal neck or back injury, place the person in a comfortable position, with their head slightly raised.
  • Control any bleeding by applying pressure to the wound with a clean piece of fabric or gauze.
  • Seek urgent medical attention.

The Concussion recognition tool 5 (CRT5) can be used to help you recognise the symptoms of concussion in both children and adults, and help you decide what to do next.

You can also use the HeadCheck app, developed by Murdoch Children’s Research Institute, to help you recognise the signs of concussion in children and adolescents.

Do not allow the person to return to the sport or activity, even if the symptoms have resolved and they feel well. Seek medical advice before a person with concussion returns to sport or activity.

How will I be diagnosed?

There is no single test to diagnose concussion.

If your doctor thinks you or your child have had a concussion, they will ask about the event that caused the head injury. If you have a video recording of the event, show it to your doctor, since it can help them understand exactly what happened.

Your doctor will perform a physical examination. They may refer you for tests such as a computerised tomography (CT) scan of you head. A CT can be used to show how severe a concussion is, and to rule out other serious injuries.

If you have signs of severe injury, your doctor may refer you to an emergency department for further investigation and observation.

What treatment will I need?

If you have had concussion, it is important to see a doctor. It’s also a good idea to stay with a responsible adult in case you have further symptoms.

Do not drive, drink alcohol or take medicines such as aspirin, anti-inflammatories, sleeping pills and sedating pain medicines until your doctor tells you it’s okay. Check with your doctor before taking any medicines that make you feel drowsy.

After having a concussion, you need to rest, both physically and mentally. Children should stay home from school and avoid screen time.

Ask your doctor when you can return to school or work. It’s important to rest, including resting your brain, after a concussion and get back to normal activities gradually. Your doctor may recommend 24 to 48 hours of complete rest, and even more time for you to return to full sporting activity.

For information on returning to sport, visit the Concussion in Sport website.

If you or your child’s symptoms gets worse in the first few weeks of recovery, or you are concerned, see your doctor.

What are my chances of full recovery after concussion?

Most people recover fully within 2 weeks, although children usually take longer to recover. Some people have symptoms for longer, especially people who have had a head injury before.

A small number of people have longer-term complications such as ‘persistent post-concussive syndrome’, which is when concussion symptoms continue for longer than 3 months after the event.

If you are concerned about ongoing symptoms after a concussion, see you doctor.

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Concussion (concussion), description of the disease on the portal Medihost.


Concussion (concussion) – reversible dysfunction of the central nervous system caused by trauma; type of traumatic brain injury.

Distinguish concussion of the spinal cord and brain. As a rule, “concussion” means a concussion of the brain.

Concussion is not currently categorized by severity. Nevertheless, for the practice of a doctor, it is important to know the variety of signs of a concussion of the brain, which can still be interpreted as a mild, moderate and severe degree of this pathology.

Causes of concussion

The cause of the pathology is mechanical impact. Concussion of the brain is typical for bruises of the head, spinal cord – for falls from a height on the head, back, buttocks, for car injuries during sudden braking.

In this case, pathomorphological changes mainly affect intracellular organelles; at the cellular level, there are areas of microscopic hemorrhages and mild edema at the border of the gray matter and pathways.

Symptoms of a brain concussion

With a mild degree of concussion, immediately after a traumatic effect, the patient begins to feel ringing in the ears, visual disturbances (in the form of a darkening of the field of vision, flickering of “flies”, blurring of the picture), partial disorientation may occur (the patient temporarily does not can understand where he is, cannot name the date of what is happening, tell about himself). The patient complains of headache, dizziness, nausea, general weakness – these symptoms disappear within a week after the injury.

Moderate concussion accompanied by loss of consciousness for a period of several minutes to an hour. It is combined with mild brain contusions. The victim has pallor of the skin, bluish tint of the lips and nails due to hemodynamic disorders. The patient who regained consciousness is inhibited, does not remember the moment of injury; General neurological symptoms are noted, similar to those with a mild concussion (headache, nausea, etc. ), which persists for 5-7 days. Hemodynamic parameters stabilize after 3-5 days.

In severe concussion, the patient does not regain consciousness for several hours. His skin is pale, earthy in color, covered with cold sweat. Muscle tone and reflexes are reduced, involuntary urination is possible.

Having regained consciousness, the patient cannot reproduce in memory the events immediately preceding the trauma, following the trauma and the moment of the trauma itself.

Headaches, dizziness are more pronounced than in milder cases and last up to three weeks. They are often accompanied by disturbances in the movement of the eyeballs, balance, vegetative-vascular reactions (cardiac arrhythmias, orthostatic hypotension, sweating). The patient may be disturbed by insomnia and nightmares. Until the final stabilization of well-being takes up to 4 months. In some cases, headaches, vestibular disorders and mental disorders persist for life. A concussion of this degree is accompanied by bruises of the brain, skull fractures, hemorrhages.

Concussion of the spinal cord after trauma causes conduction disturbances. They are manifested by flaccid (rarely spastic) paresis of the extremities, paresthesias, sometimes urinary retention may occur. In the absence of more serious damage, the symptoms resolve within a few hours.

Diagnosis of concussion

Diagnosis is made on the basis of anamnesis and clinical picture of the disease and in the absence of changes in the results of an additional examination: CT or MRI of the skull, analysis and measurement of CSF pressure. Performing CT or MRI is necessary, in particular, to exclude the syndrome of cerebral compression, which, according to the clinical picture, resembles a mild concussion: the loss of consciousness is followed by the so-called “light interval”, during which the patient’s state of health temporarily normalizes. Compression of the brain can occur during the formation of a hematoma, which, like a concussion, can be the result of an injury, but, unlike a concussion, is a life-threatening condition and requires urgent surgery.

Treatment of concussion

In case of any degree of manifestations of concussion, the victim must be hospitalized and observed for a day after the injury to exclude brain compression.

Therapy is carried out depending on the symptoms: for severe pain – analgesics, for vomiting – antiemetics. During the rehabilitation period, funds are prescribed that improve cerebral circulation, nootropic and restorative drugs.

For moderate and severe manifestations, the patient is recommended to stay in the hospital until the “severe” symptoms stop, therapy to restore systemic circulation and bed rest.

Physical and mental rest is recommended in all cases.

Concussion in children

It can be difficult to make a diagnosis based on anamnestic data due to the fact that children tend to hide the fact of an injury from their parents and doctor.

In infants, concussion is manifested by regurgitation, refusal to eat, restless behavior.

Concussion in school-age children is characterized by the onset of symptoms not immediately after the injury, but after a few minutes or hours. In this case, immediately after the injury, the child may not notice any symptoms.

Also, concussion in a child is characterized by complete blindness for several minutes.

Concussion: causes, symptoms and recommendations for the treatment of the disease. Dr. Peter

  • Directory of Diseases

July 6, 2022

A concussion is a relatively mild injury to certain brain structures due to trauma. Damage is caused by a sharp shaking, inertial force, as a result of which there are short-term functional problems in the work of the central nervous system. The key difference from more severe injuries is the absence of structural lesions, the reversible and short-term nature of the lesion.


Concussion: Causes

Most often, concussion is provoked by a direct blow to the skull, for example, in fights or during contact sports, falls with hitting the head on hard surfaces. The cause of a concussion can be a sudden impact of a load along the axis with the transmission of impulses from the spine (falling on the legs or buttocks), sudden braking or acceleration (during an accident, collisions on the run).

Since the brain is surrounded by fluid and is in a confined space, hydrodynamic shock occurs due to a sharp drop in CSF pressure. In addition to the influence of the liquid, impact and counter-impact on the skull bone from the inside is possible. As a result, there is a short-term ischemia of a certain area of ​​the brain, which can be switched off from work for a short time or there is a desynchronization of the work of the brain departments.

Concussion: symptoms

It is important to emphasize that there are no fractures of the skull and damage to brain structures visible during a CT scan during concussion. Immediately after receiving a concussion, there may be loss of consciousness lasting from a few seconds to 30 minutes. In some victims, a complete loss of consciousness does not occur, but a state of stupor is formed.

Amnesia often develops – retrograde and congrade: memories of events before the injury and during the period when consciousness was disturbed fall out. Much less often, memory is lost in relation to events that occurred after consciousness was fully restored. Often, with a concussion, nausea, headache, weakness, drowsiness, dizziness, fatigue occur. At the height of the headache, a symptom of a concussion may be vomiting, usually a single one. There may be tinnitus, pain when moving the eyeballs, severe sweating.

Possible strabismus, loss of appetite, sleep disturbances. The pressure is usually unstable, the pulse is unstable. Almost all symptoms and manifestations of concussion gradually disappear within a day after the injury. Headache, sweating, weakness, pressure fluctuations and emotional state can persist for a long time.

Why concussion is dangerous

If concussions are repeated several times, post-traumatic encephalopathies may form. There may be a violation of coordination of movements, staggering when walking, imbalance. The psyche suffers, there may be lethargy, confusion, speech problems, hand trembling. Outbursts of aggression and irritability are possible, which are poorly controlled, sensitivity to alcohol, toxins and infections suffers, depression, neuroses and phobias, paranoia, and headaches are not uncommon.

Diagnosis of concussion

Diagnosis is based on information about the injury and the events that preceded it. In addition, an examination by a neurosurgeon or neurologist is necessary. It is necessary to exclude more severe injuries, for which an x-ray of the head is performed, excluding fractures. To exclude the formation of hemorrhages and hematomas in the brain, an EEG, echoencephalography and ophthalmoscopy, and CT of the brain are performed.

How to treat a concussion

Hospitalization is required for additional examination and the exclusion of more severe injuries.

Rest is recommended for the first 24-48 hours. Of the medications for the treatment of concussion, analgesics may be required to relieve headaches, for dizziness, specific drugs are selected, sedatives and hypnotics may be recommended.

Vascular drugs, neurometabolic agents, nootropics, antioxidants, magnesium preparations, multivitamins may be indicated.


Any injury is dangerous, so care must be taken when doing housework, playing contact sports, driving and working at height.


The information on this site is not a guide to self-medication. All materials are for reference only and do not replace a visit to the doctor. If any symptoms appear, you should contact a specialist.


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  2. Yashchenko I. A., Shevchenko P. P. Modern methods of diagnosis and treatment of concussions and contusions of the brain of mild severity // MNIZH. 2013. No. 10-5 (17). Potapov A.A., Likhterman L.B., Kravchuk A.D. etc. — M.: Association of Neurosurgeons of Russia, 2016.