About severe head injuries

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 preventing falls.

Diagnosing severe head injuries

A person with a severe head injury should always be seen in an accident and emergency (A&E) department.

If any of the symptoms of a severe head injury are present, immediately go to your local A&E department or call 999 and ask for an ambulance.

The healthcare professionals treating you will first make sure you're in a stable condition, before asking some questions to help with the diagnosis and treatment of your injury.

If a friend or relative has come with you to hospital, they may be asked to describe what happened if you can’t remember.

Computerised tomography (CT) scan

You'll have a computerised tomography (CT) scan to help determine the extent of your injury and assess your risk of developing complications of a severe head injury.

The CT scan produces a detailed image of the inside of your head and shows whether there's any bleeding or swelling in your brain.

Depending on your scan results, you may be allowed to go home (see below). However, you'll usually be kept in hospital for a short period of time to make sure that your injury hasn't caused any serious problems.

The healthcare professionals treating you will assess your condition using the Glasgow Coma Scale (GCS).

Glasgow Coma Scale (GCS)

The GCS is often used to assess the severity of damage to the brain. It scores you on:

  • verbal responses (whether you can make any noise)
  • physical movements
  • how easily you can open your eyes

Your score for each is added up to give a total. A slightly different version of the GCS is used for children under five years of age.

Depending on your GCS score, head injuries are classed as:

  • minor – a score of 13 or higher
  • moderate – a score of 9 to 12
  • severe – a score of 8 or lower (the person will be unconscious)

A score of 15 (the highest possible score) means you know who and where you are, you can speak and move when asked to, and your eyes are open.

Someone with a score of 3 (the lowest possible score) will be in a coma (an unconsciousness state where a person is unresponsive and can't be woken). Their chances of survival will be small.

Based on your assessment, you may be allowed to go home or you may be referred for further testing and treatment in hospital. You may also need to have follow-up appointments at your local neurological centre or head injury clinic.

Going home

After a severe head injury, you'll only be allowed to go home if the results of your CT scan show that you don't have a brain injury and the person in charge of your care (a neurosurgeon or an A&E consultant) thinks you have a low risk of developing one.

You'll need someone to take you home, because you won't be allowed to drive until you've completely recovered. If possible, you'll also need someone to stay with you for the first 24 hours after your injury to keep an eye out for problems.

Before leaving hospital, you'll be advised about what to do and what not to do in the weeks following your injury.

Read more about recovering from a head injury

Admission to hospital

You may need to be admitted to hospital for observation following a severe head injury. This may be because:

  • scans have identified a problem
  • you have persistent symptoms of a possible neurological problem (a problem with the nervous system)
  • your GCS score hasn't returned to 15
  • you have other injuries, such as broken bones or internal bleeding 
  • you're under the influence of alcohol or drugs
  • there's no one at home to look after you

See how a severe head injury is treated for more information about what happens when you're admitted to hospital.

Treating severe head injuries

A severe head injury must always be treated in hospital to minimise the risk of complications.

Initial treatment

The healthcare professionals treating you will prioritise any potentially life-threatening injuries.

For example, they may:

  • check your airway is clear
  • check your breathing and start cardiopulmonary resuscitation (CPR or mouth-to-mouth)
  • stabilise your neck and spine – for example, by using a neck brace
  • stop any severe bleeding
  • provide pain relief if you're in a lot of pain
  • splint any fractured or broken bones (strapping them into the correct position)

Once your condition is stable, you'll have a computerised tomography scan (CT) scan to help determine the severity of your injury.

Read more about diagnosing a severe head injury.


If you need to stay in hospital for observation, the healthcare professionals treating you will regularly check:

  • your level of consciousness and how alert you are
  • the size of your pupils and how well they react to light
  • how well you can move your arms and legs
  • your breathing, heart rate, blood pressure, temperature and the level of oxygen in your blood

These checks will be made every half an hour until it's clear you know who and where you are, you can speak and move as requested, and your eyes are open. After this, checks will be less frequent.

If your CT scan results show bleeding or swelling inside your skull, a small device called an intracranial pressure (ICP) monitor may be fitted. A thin wire will be inserted into the space between your skull and the brain, through a small hole drilled into the skull. The wire is attached to an electronic device that will alert hospital staff to any changes in the pressure inside your skull.

Cuts and grazes

Any external cuts or grazes to your head will be cleaned and treated to prevent further bleeding or infection. If there are foreign bodies in the wound, such as broken glass, they'll need to be removed.

Deep or large cuts may need to be closed with stitches until they heal. Local anaesthetic may be used to numb the area around the cut so you don't feel any pain.


Neurosurgery is any type of surgery used to treat nervous system problems (problems with the brain, spinal cord and nerves). In cases of severe head injury, neurosurgery is usually carried out on the brain.

Possible reasons for neurosurgery include:

  • a haemorrhage – severe bleeding inside your head, such as a subarachnoid haemorrhage, which puts pressure on the brain and may result in brain injury and, in severe cases, death
  • a haematoma – a blood clot inside your head, such as a subdural haematoma, which can also put pressure on the brain
  • cerebral contusions – bruises on the brain, which can develop into blood clots
  • skull fracture (see below)

These problems will be identified during tests and a CT scan. If surgery is needed, a neurosurgeon (an expert in brain and nervous system surgery) may come and speak to you or your family about it.

However, as the problems listed above can be serious and may require urgent treatment, there may not be time to discuss surgery before it's carried out. In such cases, your surgeon will take the time to discuss the details of the surgery with both you and your family after the operation.


A craniotomy is one of the main types of surgery used to treat severe head injuries.

During a craniotomy, a hole is made in the skull so that the surgeon can access your brain. The procedure will be carried out under general anaesthetic, so you'll be unconscious and unable to feel any pain or discomfort.

The surgeon will remove any blood clots that may have formed in your brain and repair any damaged blood vessels. Once any bleeding inside your brain has stopped, the removed piece of skull bone will be replaced and reattached using small metal screws.

Skull fractures

Your skull may be fractured during a head injury. The CT scan will help determine the extent of the injury.

There are different types of skull fractures, including:

  • simple (closed) fracture – where the skin hasn't broken and the surrounding tissue isn't damaged
  • compound (open) fracture – where the skin and tissue is broken and the brain is exposed  
  • linear fracture – where the break in the bone looks like a straight line
  • depressed fracture – where part of the skull is crushed inwards
  • basal fracture – a fracture to the base of the skull

Open fractures are often serious because there's a higher risk of bacterial infection if the skin is broken. Depressed fractures can also be very serious because small pieces of bone can press inwards against the brain.

Treating skull fractures

Most skull fractures will heal by themselves, particularly if they're simple, linear fractures. The healing process can take many months, although any pain will usually disappear in around 5 to 10 days.

If you have an open fracture, antibiotics may be prescribed to prevent an infection developing.

If you have a severe or depressed fracture, surgery may be needed to help prevent brain damage. This will usually be carried out under general anaesthetic.

During surgery, any pieces of bone that have been pressed inwards can be removed and returned to their correct position. If necessary, metal wire or mesh may be used to reconnect the pieces of your skull.

Once the bone is back in place, it should heal naturally. Your surgeon will be able to explain the procedure you're having in more detail.

After surgery

Depending on the seriousness of your operation, you may need to recover in an intensive care unit (ICU). This is a small, specialised ward where you'll be constantly monitored. 

In an ICU, you may be placed on a ventilator, which is an artificial breathing machine that moves oxygen-enriched air in and out of your lungs.

Once you're well enough, you'll be moved to a high-dependency unit (HDU) or another ward and your condition will continue to be monitored until you're well enough to leave hospital.

Read more about recovering from a severe head injury.

Recovering from severe head injuries

When you're discharged from hospital, you'll be given information and advice to help your recovery at home.

Your recovery programme will depend on the exact nature of your injury, your individual needs and general health.

Advice for adults

If you're recovering from a severe head injury you may be advised to:

  • have someone stay with you for the first 24 hours and keep a phone to hand, in case any problems arise and you need medical help
  • get plenty of rest and avoid stressful situations
  • avoid drinking alcohol or taking illegal drugs
  • avoid taking sleeping pills, sedatives or tranquillisers (unless prescribed by your doctor)
  • take paracetamol if you have a headache, but avoid non-steroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen and aspirin (unless prescribed by a doctor)
  • avoid playing contact sports, such as football or rugby, for at least three weeks, and speak to your doctor before starting to play these sports again
  • not return to work or school until you've completely recovered and feel well enough to do so
  • not drive a car or motorbike, ride a bicycle or operate machinery until you've completely recovered and it's safe and legal to do so

When to seek medical attention

You should seek immediate medical attention if you develop any further symptoms of a severe head injury while recovering at home.

Advice for children

If your child is recovering from a severe head injury, you may be advised to:

  • give them paracetamol if they have a headache, but avoid NSAIDs, such as ibuprofen and aspirin (aspirin should never be given to children under the age of 16)
  • only give them light meals for the first day or two
  • avoid getting them too excited
  • avoid having too many visitors when they return home
  • not let them play contact sports until a doctor says it's safe to do so
  • not let them play roughly for a few days

Seek immediate medical attention if your child develops any further symptoms of a severe head injury while recovering at home.

Follow-up appointments and rehabilitation

You may be advised to see your GP the week after you're discharged from hospital, so they can check how you're coping.

You may also have a number of follow-up appointments at a head injury clinic. These will usually be with a specialist, such as a neurologist (an expert in the brain and nervous system).

Depending on how your head injury has affected you, you may need various types of treatment to help with your recovery, such as:

  • physiotherapy – to help with physical problems such as weakness, stiffness or poor co-ordination
  • occupational therapy – to help you make changes in your home or workplace if you’re struggling with everyday tasks
  • speech therapy
  • psychological therapy – such as cognitive behavioural therapy (CBT) to help you cope better if your injury has affected your mental wellbeing

Getting support

Headway, the brain injury association, is a charity that provides help and support to people affected by head injuries.

For more information about all aspects of head injuries, you can call the Headway helpline on 0808 800 2244. You can also email the helpline: helpline@headway.org.uk

Helpline staff can:

  • give you support and advice if you experience problems
  • help you find local rehabilitation services
  • advise you about other sources of support

You can also search for local Headway services. They offer a wide range of services, including rehabilitation programmes, carer support, social re-integration, community outreach and respite care (short-term support for someone who needs care – for example, to give the usual carer a break.)

Headway staff can't give medical advice. For this, see your GP or phone 111.

Complications of severe head injuries

Severe head injuries can cause serious complications, mainly because the brain can be damaged, sometimes permanently.

A particularly severe head injury can be fatal, so a person with this type of injury will be closely monitored in hospital, so that any complications that arise can be dealt with promptly and effectively.


If your skull is fractured during a head injury, you may have a greater risk of developing an infection. Skull fractures can occasionally tear the membrane (the thin layer of cells) that surrounds the brain. If this happens, bacteria can enter the wound and cause an infection.

It's important that any external wounds on your head are kept clean so they don't become infected. You may also be prescribed antibiotics.

Post-concussion syndrome

Some people may experience long-term symptoms after sustaining concussion from a head injury. This could be post-concussion syndrome.

The symptoms and effects of post-concussion syndrome can include:

  • difficulty looking after yourself
  • not being able to work
  • a persistent headache
  • dizziness
  • feeling weak
  • tinnitus (hearing sounds that come from inside the body, rather than from an outside source)
  • nausea
  • feeling very tired and problems sleeping
  • memory problems 
  • difficulty understanding others
  • poor concentration

These symptoms usually clear up in around three months, but you may need to be referred for further assessment by your GP. You may be seen by a neurologist, who specialises in problems of the nervous system (brain, spinal cord and nerves), or a psychiatrist (mental health specialist).

Read more about post-concussion syndrome.

Impaired consciousness

Some people who sustain a severe head injury enter a state of impaired consciousness, such as a coma, vegetative state or minimally conscious state.

These disorders of consciousness affect wakefulness (the ability to open your eyes and have basic reflexes) and awareness (more complex thoughts and actions, such as following instructions, remembering and communicating).

These states sometimes only last a few weeks, after which time a person may wake up or progress into a different state of impaired consciousness. However, they can last years and some people will never regain consciousness.

Brain injury

A severe head injury can damage the brain in several ways. For example, brain damage can occur as a result of increased pressure on the brain caused by a blood clot between the skull and the surface of the brain (subdural haematoma), or bleeding in and around the brain (subarachnoid haemorrhage).

After a brain injury, there's also an increased risk of epilepsy. A person who develops epilepsy following a head injury may need medication for a period of time or for life.

Brain injuries can also lead to a number of other problems, which can be temporary or permanent. The effect of a brain injury will depend on:

  • the exact location of the injury
  • the type of injury – for example, if the skull is fractured
  • the severity of the injury – for example, if surgery is required 

The different effects of a brain injury are described below.

Physical effects

Physical effects of a brain injury can include difficulty moving or keeping your balance and loss of co-ordination. You may also experience headaches or increased tiredness. 

Hormonal effects

Some head injuries can damage the pituitary gland (a small gland that sits at the base of the brain and regulates the thyroid). If the pituitary gland is damaged, it may lead to reduced hormone production and problems such as an underactive thyroid (hypothyroidism).

Sensory effects

You may lose your sense of taste and smell. You may also notice blind spots in your vision, or you may not be able to control your body temperature as well as before, so that you feel too hot or too cold.

Cognitive effects

Following a head injury, you may find it difficult to think, process information and solve problems. You may also experience memory problems, particularly with your short-term memory, and have difficulty with speech and communication skills.

Emotional or behavioural effects

After a severe head injury, you may experience changes to your feelings and behaviour. For example, you may be angrier or more easily irritated than before.

You may be less sensitive to other people’s feelings, or lose your inhibitions and behave in a way that other people consider inappropriate. You may also laugh or cry more than you did before the injury.

Getting support

As every brain injury is different, it's a good idea to seek further information about the possible effects and rehabilitation techniques. A number of charities and organisations may be able to help, including:

Last updated:
12 December 2022