Severe head injuries require immediate medical attention because there’s a risk of serious brain damage.

This topic focuses on severe head injury. Read about minor head injuries.

Symptoms of a severe head injury can include:

  • unconsciousness – where a person has collapsed and is unresponsive, even for a brief period of time
  • concussion – a sudden but short-lived loss of mental function that occurs after a blow or other injury to the head; a person with concussion may have a glazed look or appear confused, but won’t necessarily be unconscious 
  • fits or seizures  
  • difficulty speaking or staying awake
  • problems with the senses – such as hearing loss or double vision
  • repeated episodes of vomiting
  • blood or clear fluid coming from the ears or nose
  • memory loss (amnesia)
  • sudden swelling or bruising around both eyes or behind the ear
  • difficulty with walking or co-ordination

Dial 999 immediately to request an ambulance if you’re with someone who experiences any of these symptoms after sustaining a head injury. Alternatively, take them immediately to your nearest accident and emergency (A&E) department.

You should also go to hospital if someone has injured their head and:

  • the injury was caused by a forceful blow to the head at speed, such as being hit by a car or falling one metre or more
  • the person has had previous brain surgery
  • the person has had previous problems with uncontrollable bleeding or a blood clotting disorder, or is taking medication that may cause bleeding problems, such as warfarin
  • the person has been drinking alcohol or has taken drugs
  • the injury wasn’t accidental – for example, you deliberately hurt yourself or someone else hurt you on purpose

Diagnosing a severe head injury

If you’ve had a severe head injury and there’s a chance you may have a brain injury, you’ll have a computerised tomography (CT) scan to assess the seriousness of the injury.

The Glasgow Coma Scale (GCS) is often used to assess head injuries. This is a scale from 3 to 15 that identifies how serious your head injury is, based on your symptoms and whether the brain has been damaged (with 3 being most severe and 15 the least severe).

A GCS score of 13 or above would indicate a minor head injury. A score of 9 to 12 would be a moderate head injury. If a person has a severe head injury, they’ll have a score of 8 or less.

Some people with significant head injuries have a high GCS score initially, but their score decreases when they’re reassessed at a later stage.

If you have a severe head injury, you’ll be closely monitored and frequently reassessed to check your condition.

Read more about how severe head injuries are diagnosed.

Treating a severe head injury

Severe head injuries always require hospital treatment. This may involve:

  • observing the condition for any changes
  • running tests to check for further damage
  • treating any other injuries
  • breathing support (ventilation) or brain surgery

Most people are able to go home within 48 hours. However, a small number of those admitted to hospital require skull or brain surgery.

When you’re discharged from hospital, your doctor will advise you on the best way to help your recovery when you return home.

Read more about how a severe head injury is treated and recovering from a severe head injury.


A severe head injury can result in pressure being placed on the brain because of bleeding, blood clots or a build-up of fluid. This can sometimes lead to brain damage, which can be temporary or permanent.

A severe head injury can also cause other potentially serious complications, including:

  • an infection after a skull fracture 
  • impaired consciousness
  • brain injury

Around 1 in every 2,000 people who attend an A&E department with a head injury dies as a result of their injury.

Read more about complications after a severe head injury.

Preventing head injuries

It can be difficult to predict or avoid a head injury, but there are some things you can do to reduce the risk of serious injury. These include:

  • ensuring your home (or those of elderly relatives) are free of trip hazards that could cause a fall, such as loose carpets or unnecessary items on the floor
  • “childproofing” your home – for example, by ensuring young children can’t reach windows or balconies
  • using the right safety equipment for work, sport and DIY

Wearing a safety helmet during certain activities, such as skiing or cycling, may also help to prevent a serious head injury.

Read more about cycle safetypreventing falls and preventing accidents to children in the home.