Acquired brain injury (ABI)
Key facts
- An acquired brain injury (ABI) is brain damage that can result from many different causes including injury, illness or substance abuse.
- An ABI may cause weakness, seizures, memory problems and emotional changes.
- Diagnosis usually involves brain scans and tests of memory, thinking, and daily tasks.
- Treatment for an ABI depends on the cause and often includes rehabilitation programs.
- Support is available for people with an ABI and their family and caregivers.
What is an acquired brain injury (ABI)?
An acquired brain injury (ABI) is damage that occurs to your brain at any time during your life after birth. This damage could happen in many ways and can cause various problems for the person affected.
ABI is different from an intellectual disability or a mental illness.
What causes an ABI?
An ABI may be caused by:
- trauma or injury to the head (sometimes called a traumatic brain injury)
- stroke
- drugs, alcohol or poisons
- not getting enough oxygen to the brain for a long time (for example, a near-drowning)
- infection
- tumours
- degenerative brain conditions such as Parkinson's disease, Alzheimer's disease or another form of dementia
What are the symptoms of an ABI?
An ABI can affect people in many different ways.
Some people have physical symptoms, including:
- weakness, shaking, stiffness or poor balance
- tiredness
- changes in sleep patterns
- seizures
- headaches
- changes in vision, smell or touch
Call an ambulance for anyone who has had a head injury and is experiencing a change in their level of consciousness (eg. slurred speech, seizures, unable to be roused).
Some people have changes in their thinking or learning abilities, including:
- problems with memory
- problems with concentration or attention
- difficulty with planning or organisation
- confusion
- difficulty with communication, such as keeping a conversation going
Some people have problems with controlling their behaviour or emotions, including:
- mood swings
- being irritable or feeling on edge
- changes in personality
CHECK YOUR SYMPTOMS — Use the Symptom Checker and find out if you need to seek medical help.
How is an ABI diagnosed?
You often need to have a brain scan to be diagnosed with an ABI. This helps doctors check the level of any brain damage. Depending on the cause of the ABI, other tests might be needed.
Medical professionals may test your memory, thinking and how well you manage everyday tasks. These results are used to find out what kind of problems you're having, and what support you will need.
When should I see my doctor?
You should see your doctor if you are having symptoms of an ABI.
FIND A HEALTH SERVICE — The Service Finder can help you find doctors, pharmacies, hospitals and other health services.
How is an ABI treated?
Treatment will depend on what has caused your ABI.
You will also need treatment for any specific problems your ABI causes. This involves a rehabilitation program that focuses on the areas of life in which you're having problems.
Rehabilitation takes time. The biggest improvements happen in the first few months after an injury, but recovery can continue for years afterwards. Some people may have to live with some of the effects of an ABI forever.
Living with an ABI
If you have an ABI, you might have specific goals for your recovery, such as regaining lost skills and returning to work or study. This can be challenging.
If you have an ABI, look after your health and wellbeing to help your brain recover.
A National Assistance Card is useful for emergencies and daily situations where you may need assistance.
How do I care for a person with an ABI?
Living with an ABI can be an adjustment for family and carers as well as for the person with a brain injury.
Families and carers provide much needed support to a person living with an ABI. It is normal for carers of a person with ABI to put themselves last.
Caring for someone with an ABI can often mean taking sole responsibility for the household and the finances. You may feel overwhelmed, confused and shocked.
As a carer, it's important that you maintain your health and wellbeing.
Some wellbeing tips for carers include:
- asking for help when you need it
- taking time for yourself
- getting regular exercise, eating and sleeping well
- making sure you keep in contact with family and friends
- attending carer support groups
- acknowledging and dealing with difficult feelings
Support organisations are available if you are caring for someone with an ABI.
Resources and support
If you need more support, speak with your doctor, as they may be able to help you find what you need.
The Brain Foundation has a fact sheet on ABI and treatment options.
Call Synapse on 1800 673 074 — for information and support for people affected by brain injury and disability. ABI: The Facts is their practical guide to understanding and responding to acquired brain injury. Synapse also has a wide range of information for carers.
Call Brain Injury Australia on 1800 BRAIN1 (1800 272 461) — or download a range of fact sheets about acquired brain injury and how to access support.
You can also call the healthdirect helpline on 1800 022 222 (known as NURSE-ON-CALL in Victoria). A registered nurse is available to speak with you 24 hours a day, 7 days a week.
Learn more here about the development and quality assurance of healthdirect content.
Last reviewed: August 2025
