Nocturnal seizures are seizures that happen while a person is asleep. They can cause unusual nighttime behavior, such as waking for no reason or urinating while sleeping, as well as jerking and shaking of the body.

Nocturnal seizures are usually a type of seizure called a tonic-clonic seizure. Most people with nighttime seizures of this kind have epilepsy.

In this article, learn more about nocturnal seizures, including the causes, symptoms, and treatments.

Nocturnal seizures are rare and usually mean a person has epilepsy.

Various chemicals trigger regular electrical activity that plays a role in everyday thinking, movement, and other brain functions. During a seizure, a sudden surge of unusual electrical activity causes a person to lose control of some of these functions.

There are many different types of seizures, and any can happen during sleep. Some wake from sleep with an aura before having a complex partial seizure. It’s not uncommon to have these episodes without memory of them the next day.

Most nocturnal seizures are tonic-clonic. Doctors used to call tonic-clonic seizures grand mal seizures. They typically last less than 5 minutes.

During the tonic phase, a person’s muscles stiffen. This can cause them to bite their tongue or lose control of their bladder or bowels.

During the clonic phase, their muscles may twitch. Immediately after the seizure, it may be difficult to wake the person.

Lack of sleep is a common seizure trigger among people with epilepsy, so nocturnal seizures that disrupt sleep may increase the risk of further seizures.

During a nocturnal seizure, a person may:

  • cry out or make unusual noises, especially right before the muscles tense
  • suddenly appear very rigid
  • wet the bed
  • twitch or jerk
  • bite their tongue
  • fall out of the bed
  • be difficult to wake after the seizure
  • be confused or display other unusual behaviors after a seizure
  • wake suddenly for no apparent reason

Not all people with nocturnal seizures know they have them. Sometimes, the only symptom is a headache or a bruise upon waking.

Following a seizure, a person may feel exhausted or sleep-deprived. This can cause them to be sleepy or irritable during the day.

Nocturnal seizures usually occur:

  • right after a person falls asleep
  • right before they awake
  • right after they awake

Epilepsy can cause nighttime seizures. Epilepsy is an umbrella term that refers to many different types of seizure disorders.

Knowing a person has epilepsy does not explain why they have seizures. Doctors diagnose a person with epilepsy if they have two or more seizures that are not clearly caused by something else, such as a fever or alcohol withdrawal.

Some potential causes of epilepsy include:

Some people are at higher risk of developing epilepsy, including:

  • people with a family history of seizures
  • people who are age 40 or older
  • those with sleep disorders
  • abnormal pregnancy
  • people who snore
  • history or being hospitalized

Certain types of epilepsy are more likely to cause nocturnal seizures. They include:

  • awakening tonic-clonic seizures
  • childhood benign rolandic epilepsy
  • Landau-Kleffner syndrome
  • frontal lobe epilepsy
  • juvenile myoclonic epilepsy

Distinguishing nocturnal seizures from other sleep behavior, such as sleepwalking or night terrors, can be challenging.

People who live alone may wake up tired. However, they do not know that they have seizures. If a person does not experience daytime seizures, they may be unaware they are at risk for nighttime seizures.

A person who has unusual nighttime behavior, headaches in the morning, or unexplained mood changes should see a doctor.

Doctors usually diagnose epilepsy with an electroencephalogram (EEG), which is a test that measures electrical activity in the brain. In some cases, a doctor may recommend MRI or CT scans to see if there is an area of brain injury or a tumor in the brain.

When a person only experiences nighttime seizures or is not sure whether their nighttime experiences are seizures, a doctor may recommend a sleep study. Sleep studies can rule out other issues, such as sleep apnea.

Several types of childhood epilepsy can cause nocturnal seizures.

Benign rolandic epilepsy, the most common form of childhood epilepsy, usually disappears in adulthood. The primary symptom is nighttime seizures.

Children with this form of epilepsy may also have migraine or behavioral issues. Most children with this form of epilepsy have a family history of seizures.

Juvenile myoclonic epilepsy, sometimes called Janz syndrome, typically begins in adolescence, and the seizures may be short at first. Doctors do not know what causes this type of epilepsy. However, it may be genetic.

Not all nighttime seizures in children mean the child has epilepsy. Between 2–5% of children under 5 years of age in the United States experience febrile seizures, which happen when they have a fever.

Febrile seizures are usually harmless, and they typically resolve once the fever subsides. However, it is essential to see a doctor to rule out other causes, such as a brain injury or infection.

Nocturnal seizures are potentially dangerous and increase the risk of dying from epilepsy. Having a seizure while sleeping can also make a person prone to injuries.

People who experience nighttime seizures are more likely to experience low blood oxygen during and after the seizure. They are also more likely to continue to experience unusual brain activity after the seizure.

While this can be frightening, epilepsy is usually treatable. Controlling seizures greatly reduces a person’s risk of complications.

The right treatment depends on several factors, including:

  • type of seizures
  • severity of the seizures
  • frequency of the seizures
  • a person’s age
  • overall health

Possible treatments include:

  • antiseizure medication
  • avoiding seizure triggers, such as sleep deprivation
  • a high fat, low carbohydrate diet, or ketogenic diet
  • a vagus nerve stimulator, or surgical implant that sends electrical impulses to the brain

Tracking symptoms and triggers can help with identifying any patterns in the symptoms and whether the treatment plan is working.

People who have nocturnal seizures may also wish to take measures to prevent injuries. These can include:

  • choosing a low bed frame or placing the mattress on the floor
  • putting a safety mat, such as those for gymnastics, on the floor next to the bed
  • using wall-mounted lamps rather than table lamps
  • keeping furniture away from the bed
  • using a nocturnal seizure monitor that alerts a loved one when a person has a seizure

Below are some frequently asked questions about nocturnal seizures.

Why do so many seizures happen during sleep?

There are many theories as to why seizures happen during sleep. However, the exact reason is unknown.

It is thought that excessive hypersynchronous activity in the brain during sleep may contribute. This may make a person with epilepsy more likely to have a seizure.

How do you know if you are having seizures in your sleep?

If you have seizures during your sleep, you may not be aware of them. A loved one may notice abnormal noises or jerking motions. Other symptoms include:

  • wetting the bed
  • falling out of bed
  • waking suddenly for no reason
  • waking up tired
  • waking up sore

Can nocturnal seizures be fatal?

Nocturnal seizures are potentially dangerous and can increase the risk of dying from epilepsy. Having a seizure while sleeping can also make a person prone to injuries.

If you or someone you know experiences nocturnal seizures, it is important to seek medical help immediately. Treatment can greatly reduce the risk of complications.

Should you sleep after a seizure?

It is generally recommended to let people sleep after a seizure to allow the body to rest.

However, if you have nocturnal seizures, it is important to take measures to prevent injuries. This can include choosing a low bed frame or placing the mattress on the floor.

Nocturnal seizures are potentially dangerous. For people with no previous history of seizures, they may be the first sign of epilepsy.

No matter how many nighttime seizures a person has or what medication they take, it is vital to see a doctor for any symptoms of nighttime seizures promptly.

Controlling nighttime seizures can significantly reduce the risk of epilepsy complications. A full diagnosis can also rule out other causes of troubling symptoms at night.

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