Concussion (mild TBI)

Concussion is a blow to the head or body that causes the brain to shake inside the skull. This can change the way your brain normally works. It is a type of mild Traumatic Brain Injury (mTBI) where the person is usually unconscious for less than 30 minutes. However, it is possible to have a concussion without being unconscious.


Common symptoms are headaches, confusion, nausea, dizziness, memory problems and fatigue. Sometimes people complain of “just not feeling like themselves.” If you or a loved one notices any of these symptoms, you should seek medical attention immediately.

Recovery Times

Recovery times vary. For most people, the symptoms are temporary and may resolve in a few hours or days. For a few people the effects can be much more severe and longer lasting.

When the effects of a head injury persist in this way, over weeks, months or sometimes years, the person may be experiencing Post Concussion Syndrome (PCS). After any suspected concussion, it is important to get your doctor’s advice on the best treatment.  

Post Concussion Syndrome (PCS)

Post Concussion Syndrome (PCS) is a complex disorder in which various symptoms — such as headaches and dizziness — last for weeks and sometimes months after the injury that caused the injury. Most people recover from a concussion relatively quickly within a few hours or days with rest and sleep. Most people are able to return to work within two weeks of the injury. Symptoms can last longer for some people, and can seem more severe than perhaps a casual observer would guess from the initial injury. PCS describes the situation where someone is experiencing the more severe and long lasting after-effects of a relatively mild blow to the head.

Diagnosis and Risk Factors

Diagnosing PCS is hard. The symptoms are also associated with other problems, including work or relationship stress, drug and alcohol issues, depression, a virus, or a more serious psychological or psychiatric problem. Whether you get PCS or not does not appear to be linked to the severity of the injury. Some people experience many concussions and do not get PCS. Risk factors include:

  • Multiple previous head injuries
  • A history of serious emotional or psychiatric problems
  • Alcohol or solvent abuse
  • A demanding occupation
  • Age (children, teenagers, and the elderly are more vulnerable)

For more information on PCS, see this page at which also has a factsheet for download.

Is concussion dangerous?

Mild Traumatic Brain Injury is rarely dangerous on its own and does not result in death. However, having a concussion can be a risk factor for more serious conditions, such as Second Impact Syndrome or for Chronic Traumatic Encephalopathy.

Although most concussions result in only temporary effects, you should take all injuries seriously. If you experience a head injury, mild or otherwise, in the course of sporting activity for example, make sure you get medical attention immediately. There are guidelines for various sports to ensure that you do not put yourself in further danger.

What is Second Impact Syndrome?

Second impact syndrome describes the situation in which an individual gets a second injury before the symptoms from a previous injury have resolved. In the case of second impact syndrome, the brain swells rapidly and dangerously, resulting in death or severe brain injury.

Second Impact Syndrome is rare, but it is often fatal.

What is Chronic Traumatic Encephalopathy (CTE)?

Chronic Traumatic Encephalopathy (CTE) is a progressive disease of the brain found in athletes and other people with a history of repeated head injury, including concussions. The symptoms include memory loss, confusion, impaired judgment, impulse control problems, aggression, depression, and, eventually, progressive dementia.

CTE historically has been most associated with boxing and American Football, but more recent studies have identified other sports which present risk of CTE, including Rugby, Football, Hockey, Wresting, Equestrian sports and others.

What Sporting Guidelines are there?

International Guidelines on Concussion

The international community have agreed an overall approach to dealing with concussion in sport, which is contained in the document:

Consensus statement on concussion in sport: the 5th International Conference on Concussion in Sport held in Berlin, October 2016

Concerned about concussion?

If you think you may be suffering from the effects of concussion, seek medical help immediately. Consult a doctor or your GP. If you have prolonged aftger-effects from a blow to the head, see the section on Post Concussion Syndrome above.

Irish Sporting Guidelines

Irish Rugby concussion protocols are at Irish Rugby | IRFU Concussion Protocols has much useful materia
GAAThe GAA website has an extensive section on the management of concussion at Concussion | GAA DOES
FootballThe FAI has  a section on their website devoted to management of concussion at
HockeyThe Irish Hockey Association has a set of guidelines at CONCUSSION POLICY – Hockey Ireland