Sudden Unexpected Death in Epilepsy – SUDEP

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Sudden Unexpected Death in Epilepsy (SUDEP) is when a person with epilepsy dies suddenly and prematurely and no reason for death is found.

SUDEP deaths are often unwitnessed with many of the deaths occurring overnight during sleep. There may be obvious signs a seizure has happened, though this isn’t always the case.

The cause of SUDEP is not yet clear. Researchers are investigating a range of possibilities such as the effect of seizures on breathing, the heart and arousal.

SUDEP occurs in approximately 1 per 1000 people with epilepsy (1 in 4,500 children).

Having active seizures can put you at risk, and there are certain types of seizures which can increase a person’s risk of SUDEP. Much is already being done to try to understand what causes SUDEP, but more research is continuing.


What is my risk of SUDEP?

We don’t know exactly what causes SUDEP to happen, or who will be affected. But researchers have identified key risk factors that can increase risk of SUDEP – and in some cases, there are positive things that can be done to reduce risks.


As a general group, people living with epilepsy are at a 1 in a 1000 risk of SUDEP per year. This risk varies depending on your seizures, for example:

  • The risk increases if you have tonic clonic seizures, especially if they happen at night or when asleep
  • The more frequent the tonic clonic seizures, the higher the risk
  • Although SUDEP is more common in people with frequent seizures it has also occurred in people who have had very few seizures.
  • People with absence or myoclonic seizures are not known to have an increased risk for SUDEP

Risk levels vary between people with epilepsy, and they can change over time; it is important you discuss your risks and concerns with your doctor who can help you assess your own risks and put steps in place to reduce them.

Your lifestyle and treatment choices are important. For example, you may be in a high-risk group but have options to reduce that risk, such as surgery for epilepsy or improved medications. Or you may be at low risk but your treatment or lifestyle choices put you at greater risk, for instance deciding to make medication changes without speaking to your doctor or drinking excessive alcohol.

Key risk factors for SUDEP:

There are known risk factors which increase the chance of death in people with epilepsy. Many of these risk factors can change over time, or can be changed to improve seizure control and reduce risks.

The main risks include:

  • tonic-clonic seizures
  • tonic-clonic seizures during sleep
  • sleeping or living alone

Other factors that can influence your risk are:

  • medication changes or forgetting medication
  • frequent seizures
  • seizures begin at a young age or the person has had epilepsy for more than 15 years
  • males between 20-40 years
  • drinking excessive alcohol or substance abuse
  • depression or psychiatric illness
  • intellectual disability

Absence or myoclonic seizures, are not proven to be associated with increased SUDEP risk. However, if you have these seizures and do not take your medication as prescribed, the you may be at risk for tonic-clonic seizures.

Taking medication as prescribed is important even when you are not experiencing tonic-clonic seizures.


If you want to know more about your individual risk, ask to go through a SUDEP and Seizure Safety Checklist with an epilepsy nurse or your doctor.

Can I change the risk of SUDEP? 

Many risks can be lessened. The most important step you can take to avoid SUDEP is to try and reduce the number of seizures you have.

There are positive steps you can take to help reduce your risks; Check out our Taking Action Against Risk pages for tips and free resources to help.

What is the risk of SUDEP for children with epilepsy? 

The risk of SUDEP for children with epilepsy is lower than adults (approximately 1 in every 4,500 children with epilepsy), but the risk factors are the same as for adults. It is something to be aware of and discuss with your child’s doctor.

Can safety devices help? 

There are a number of devices and monitors for night-time seizure monitoring now available for use in the home. They are designed to recognise a seizure or changes in breathing patterns or heart rate. There are various types of devices and most are for detection of convulsive (tonic clonic) seizures. If a seizure happens, an alarm is triggered so that either a family member, friend or emergency services can be notified.

Monitors, alarms and safety products don’t guarantee safety or detection of all seizures, but they can provide peace of mind for some people.

Some families have found monitors to be a useful part of a risk reduction plan. Speak to your doctor or epilepsy nurse about whether a device is something that you might choose to use.

Read more about individual devices on our Epilepsy Products page or contact Epilepsy Action Australia to speak with an Epilepsy Nurse.

I have lost someone to SUDEP 

Epilepsy Action Australia offers support and information to families and friends who have lost a loved one due to SUDEP or other epilepsy-related death. Please do not hesitate to make contact with us here.

We also have a Facebook group dedicated to those who have lost their lives due to epilepsy, and, to their family and friends who need to find the comfort and strength to keep living Epilepsy: In Memoriam – you are not alone

You may like to help further research into epilepsy-related deaths and SUDEP by sharing information about the loss of your loved one. The Epilepsy Deaths Register is an international register that gathers information from families, friends and doctors to build a holistic picture of the circumstances around your loss to help educate others about epilepsy-related deaths. For more information click here.

Where can I find out more information about research on SUDEP?

The resource SUDEP Global Conversation contains a collection of key SUDEP research summarised into quick easy to read extracts, as well as highlighting families stories of those affected by SUDEP. Click here to read more on the Global Conversation or here for SUDEP Research Updates.

SUDEP Action UK are also a good source of information

Here is our SUDEP Factsheet