Healthdirect Free Australian health advice you can count on.

Medical problem? Call 1800 022 222. If you need urgent medical help, call triple zero immediately

healthdirect Australia is a free service where you can talk to a nurse or doctor who can help you know what to do.

beginning of content

Coma

4-minute read

What is a coma?

When someone is in a coma, they are unconscious, they do not respond, and they cannot be woken up. A coma is a medical emergency and the person in the coma will need immediate treatment in hospital.

Someone who is in a coma is alive but completely unresponsive to the world around them. There is very little activity in their brain.

Some people in a coma can breathe on their own but others will need help. They won’t be able to cough or swallow and they won’t respond to pain, light or sound. Their eyes will be closed and they won’t be able to move or communicate.

There are different levels, or depths, of coma. The hospital will measure the depth of the coma based on the person’s responses, how long they have been in a coma and how well their body is functioning. They do this to track the person’s level of consciousness over time.

Some people may become more alert and wake up but show no signs of awareness. This is called post-coma unresponsiveness (previously called persistent vegetative state). People can stay like this for a long time and may improve, but they are unlikely to make a full recovery.

What are the most common causes of coma?

The causes of coma include:

Sometimes people are put into a medically induced coma with medicines. This helps their brain to keep functioning after an injury and saves the patient from feeling extreme pain.

What care does someone in a coma need?

Someone in a coma needs intensive care in hospital. They may need help with breathing, they will be fed through a tube and they will receive blood and fluids through a drip inserted into the vein. The cause of their coma will also need to be treated to prevent further brain damage.

They will need medical support to stop their body deteriorating and to prevent complications such as pressure sores and ulcers, infections or blood clots in the legs, including deep vein thrombosis (DVT). Their limbs will need to be exercised gently to prevent them from getting tight. They may also need medicine to calm them down if they get restless.

Although it has not been scientifically proven, many families of people who have been in a coma say that talking to them, playing their favourite music and stimulating them can help them to wake up.

What is the expected outcome of a coma?

Comas usually don’t last longer than 4 weeks, although cases have been recorded where people stay in a coma for several years. When someone comes out of a coma, they become more aware and regain consciousness gradually. After they wake up, they might be very confused about the day and time, where they are and who they are.

Their long-term expected outcome (prognosis) will depend on the brain injury that caused the coma. Some people, such as people who were in a diabetic coma, will make a full recovery. Others may have permanent brain damage and will need therapy and support for the rest of their lives.

People with post-coma unresponsiveness can be in this state for months or years. They may gradually pass into a minimally conscious state, where they are more aware and may be able to communicate.

Unfortunately, some people never recover from a coma. If the coma lasts more than a few weeks, their family may be asked to make decisions about whether to continue medical support. It’s easier to make the decision if families members have discussed their wishes earlier.

Resources and support

You can find more information about brain injury and coma from the following organisations:

If you know someone in a coma, you can register their details on the Australian Register of Disorders of Consciousness (ARDOC).

Sources:

WebMD (Coma), Brain Foundation (Coma), Synapse (Coma and brain injury), NHMRC (Ethical guidelines for the care of people in post-coma unresponsiveness (vegetative state) or a minimally responsive state), Merck Manual (Stupor and Coma), Brain Foundation (Vegetative State (Unresponsive Wakefulness Syndrome))

Learn more here about the development and quality assurance of healthdirect content.

Last reviewed: May 2021


Back To Top

Need more information?

These trusted information partners have more on this topic.

Top results

Coma - Brain Foundation

Coma (See also Acquired Brain Injury, Stroke) Description Coma is a state of unconsciousness in which a patient does not react with the surrounding environment

Read more on Brain Foundation website

Coma and brain injury - Synapse

Coma is generally the result of damage or interference with particular structures of the brain. During a coma, a person is in a state of unconsciousness.

Read more on Synapse - Australia's Brain Injury Organisation website

Diabetic coma - Better Health Channel

betterhealth.vic.gov.au

Read more on Better Health Channel website

Vegetative State - Brain Foundation

Vegetative State (Unresponsive Wakefulness Syndrome) Description A vegetative state is when a person is awake but showing no signs of awareness

Read more on Brain Foundation website

Minimally Conscious State - Brain Foundation

Minimally Conscious State Description The minimally conscious state is a defined asseverely altered consciousness in which minimal but definite, sustained and/or reproduciblebehavioral evidence of awareness of self or environment is demonstrated

Read more on Brain Foundation website

Acquired Brain Injury - Brain Foundation

Acquired Brain Injury (Brain Injury, Head Injury, Traumatic Brain Injury, TBI) Description Brain injury includes a complex group of medical and surgical problems that are caused by trauma to the head

Read more on Brain Foundation website

Creutzfeldt-Jakob Disease - Brain Foundation

Creutzfeldt-Jakob Disease Read more at Virtual Medical Centre Description Creutzfeldt-Jakob disease (CJD) is a rare brain disorder

Read more on Brain Foundation website

Acquired brain injury - Better Health Channel

betterhealth.vic.gov.au

Read more on Better Health Channel website

Ketoacidosis: a complication of diabetes - MyDr.com.au

Diabetic ketoacidosis (DKA) is a serious condition that can occur as a complication of diabetes. People with DKA have high levels of glucose and ketones in the blood, making it more acidic than usual.

Read more on myDr website

Hyperglycaemia in diabetes - MyDr.com.au

Hyperglycaemia means too much sugar (glucose) in the bloodstream. For someone with diabetes it means their diabetes is not well controlled.

Read more on myDr website

Healthdirect 24hr 7 days a week hotline

24 hour health advice you can count on

1800 022 222

Government Accredited with over 140 information partners

We are a government-funded service, providing quality, approved health information and advice

Australian Government, health department logo ACT Government logo New South Wales government, health department logo Northen Territory Government logo Government of South Australia, health department logo Tasmanian government logo Victorian government logo Government of Western Australia, health department logo