Sudden unexpected death in epilepsy

Key points

  • Sudden unexpected death in epilepsy is referred to as SUDEP.
  • SUDEP is rare.
  • Take your seizure medicine as prescribed to lower your chance of SUDEP.
Unhappy woman talking on phone.


For some people living with epilepsy, the risk of sudden unexpected death in epilepsy (SUDEP) is a major concern.

SUDEP refers to deaths in people with epilepsy that are not caused by injury, drowning, status epilepticusA, or other known causes.1

SUDEP is rare

Researchers are studying SUDEP, but it's hard to know exactly how many people with epilepsy die because of SUDEP each year.

Experts estimate that for every 1,000 U.S. adults with epilepsy, one may die from SUDEP each year.2

SUDEP is even less common in U.S. children. For every 4,500 children 17 years or younger with epilepsy, one may die from SUDEP each year.2

Causes of SUDEP

Most SUDEP deaths occur with a generalized seizure during sleep.1

There are a number of reasons why someone with epilepsy may die of SUDEP:1

Breathing problems—a seizure may cause a person to have pauses in breathing, called apnea. If these pauses last too long, it can reduce the oxygen in the blood. Someone can also suffocate if the airway is covered or obstructed.

Heart problems—a seizure may cause a dangerous heart rhythm or very slow heart rate.

Other causes—SUDEP may result from a combination of breathing problems, abnormal heart rhythms, or other unknown causes. Problems with brain function and genetic disorders may also contribute to SUDEP.

Risk factors for SUDEP

Main risk factors

The main risk factors for SUDEP are:

Possible risk factors

Other possible risk factors may include:1

  • Having seizures from a young age.
  • Living with epilepsy for many years.
  • Being a male.
  • Missing doses of seizure medicine.
  • Having seizures during sleep.


Talk to your health care provider

If you have epilepsy, ask your health care provider to discuss your risk of SUDEP.

Senior woman discusses with doctor
Tell your health care provider if you are still having seizures while taking your epilepsy medicine.

Take your seizure medicine as prescribed

This is the most important thing you can do to reduce your risk of SUDEP.

If you are taking seizure medicine and still having seizures, talk to your health care provider right away.

If your seizures continue, consider seeing an epilepsy specialist. You can search for a doctor or find an epilepsy center close to you through CDC's partner websites.

Other ways to reduce your risk

  • Avoid seizure triggers.
  • Learn ways to self-manage or reduce your seizures.
  • Get enough sleep.
  • Train adults in the house in seizure first aid.

What CDC is doing

CDC supports the Sudden Death in the Young (SDY) Case Registry, which identifies and counts the number of deaths from SUDEP among young people (20 and younger). The goal of this project is to understand the causes of death so we can prevent SUDEP.

  1. Status epilepticus occurs when a seizure lasts more than 5 minutes, or when seizures occur back to back, with no recovery in between.
  1. Devinsky O, Hesdorffer DC, Thurman DJ, Lhatoo S, Richerson G. Sudden unexpected death in epilepsy: epidemiology, mechanisms, and prevention. Lancet Neurol. 2016;15(10):1075–1088.
  2. Harden C, Tomson T, Gloss D, et al. Practice guideline summary: sudden unexpected death in epilepsy incidence rates and risk factors: report of the Guideline Development, Dissemination, and Implementation Subcommittee of the American Academy of Neurology and the American Epilepsy Society. Neurology. 2017;88(17):1674–1680. doi:10.1212/WNL.0000000000003685