Seizures While You Sleep: How To Diagnose Nocturnal Seizures

Did you know that seizures can happen while you sleep? Often a result of epilepsy, these nighttime seizures can be hard to diagnose and are often misattributed to the symptoms of parasomnia sleep disorders. 

Epilepsy and seizures

A seizure refers to a sudden and uncontrolled electrical disturbance in the brain that results in uncontrollable movements and behaviors. The most common reason for seizure occurrence is a condition called epilepsy. Epilepsy is relatively prevalent, with 1 in 26¹ people developing it in their lifetime. 

The two main types of seizures that occur with epilepsy are:

• Generalized seizures - In this type of epileptic seizure, the electrical disturbance occurs in both hemispheres of the brain. Generalized seizures can be classified into grand mal (jerking motions, stiffened body, unconsciousness) and petit mal (small hand/arm movements, blinking, staring).

• Partial (focal) seizures - This type of epileptic seizure only occurs in one hemisphere of the brain, meaning that patients can be awake and conscious when they occur. Partial seizures tend to affect patient behavior, responsiveness, and, at times, consciousness. 

Seizures during sleep

There is a range of different epileptic disorders that can result in nocturnal seizures. The types of epilepsy that are commonly associated with seizures during sleep include:

• Juvenile myoclonic epilepsy (JME)

• Epilepsy with generalized tonic-clonic alone 

• Childhood epilepsy with centrotemporal spikes (benign rolandic epilepsy)

• Electrical status epilepticus of sleep (ESES or CSWS)

• Landau-Kleffner syndrome (LKS)

• Frontal onset seizures (e.g., nocturnal frontal lobe epilepsy) 

It’s important to note that nocturnal seizures can be a symptom of all types of epilepsy and can also occur in people who do not have epilepsy. 

Some people may find that their seizures only occur during sleep, while others may experience them both awake and asleep. Nocturnal epilepsy is the term used to describe people who only experience nocturnal seizures. 

When do seizures occur during sleep?

Research² tells us that you’re most likely to experience a nocturnal seizure between 5 AM and 6 AM, near the end of your sleep. You’re least likely to experience one during the first 1–2 hours of sleep. 

We also know that you’re more likely to experience a nocturnal seizure during the non-REM stages of sleep. 

The common symptoms of a nocturnal seizure

Nocturnal seizures can be harder to recognize than others, largely because the person is not conscious, and there will likely be no one awake and around to notice them. 

Typical symptoms of nocturnal seizures include:

• Tongue biting 

• Jerking/violent body movements 

• Suddenly waking for unclear reasons 

• Shouting or screaming 

Post-nocturnal seizure symptoms³ that could indicate you have experienced a nocturnal seizure the previous night include:

• Difficulty concentrating 

• Drowsiness/tiredness

• Stiff muscles 

• Increased frequency of daytime seizures 

What causes nocturnal seizures?

We know that seizures result from electrical misfiring in the brain, and it’s thought that nocturnal seizures occur due to changes in sleep stages. There are many changes to our brain's electrical waves during sleep, especially during the different stages of sleep — these may trigger the onset of nocturnal seizures. 

We see this in the fact that seizures are much less likely during REM sleep than in the different stages of non-REM sleep. The non-REM stages also show variation in seizure frequency among themselves. 

The process of diagnosing nocturnal seizures

Because of when they occur, nocturnal seizures can be difficult to diagnose. When the symptoms of nocturnal seizures are diagnosed, they can sometimes be misattributed to other conditions like sleepwalking, night terrors, or anxiety. 

Diagnosis of nocturnal seizures may include your doctor:

• Taking a family history 

• Evaluating your medical history 

• Taking a CT scan, EEG, or MRI of your brain 

• Measuring your nocturnal seizures through an overnight stay in a sleep clinic 

Once diagnosed, treatment options for nocturnal seizures typically include the same antiepileptic medications as for daytime seizures, but you may be prescribed a higher dose before bed. 

Safer sleeping habits for sleep seizures 

If you are experiencing nocturnal seizures, there are a few things you can do to ensure you’re safer while you sleep: 

• Choose a bed that is low to the ground to avoid high falls 

• Move other furniture a safe distance away from your bed, so you don’t hit it if you fall out

• Put soft mats around your bed for a safer landing in case of a fall 

• Install wall-mounted lamps to remove the danger of touching or hitting a hot bedside lamp 

• Never smoke in bed 

• Install night-time seizure monitoring devices to help you keep track of your nocturnal seizure frequency 

• Use specially designed anti-suffocation pillows 

• Ensure that anyone you live with knows how to put someone in the recovery position and what to do in an emergency 

The lowdown

Because of when they occur, nocturnal seizures can be difficult to diagnose. Understanding the symptoms and post-effects of nocturnal seizures can help you determine if you might be experiencing seizures while you sleep and if you need medical help. 

People also ask

How often do nocturnal seizures occur?

Nocturnal seizures can occur around 3–4 times a night as the sleep cycle repeats.

What are the symptoms of nocturnal seizures?

The symptoms of nocturnal seizures can be hard to recognize but include:

• Wetting the bed

• Tongue biting 

• Jerking/violent body movements 

• Suddenly waking for unclear reasons 

• Shouting or screaming 

• Difficulty concentrating 

• Drowsiness/tiredness

• Stiff muscles 

• Increased frequency of daytime seizures

Why do nocturnal seizures happen?

Nocturnal seizures happen when electrical activity in the brain goes haywire, causing involuntary movements and behaviors during sleep.