Narcolepsy vs epilepsy - what’s the difference?

Narcolepsy and epilepsy are two conditions that can affect your brain, the way you behave, and how you feel. While their underlying causes are different, the symptoms of the two disorders may look quite similar - and could even be confused with one another. And this is why it’s important to learn about the differences between narcolepsy and epilepsy.

Here’s everything you need to know about narcolepsy and seizures caused by epilepsy. 

Narcolepsy vs epilepsy 

Let’s learn about what these two conditions are, and how they affect people who live with them. 

What is narcolepsy?

Narcolepsy is a condition which means people’s brains are unable to properly regulate how they sleep and stay awake. This means they may:

• Feel sleepy much of the time
• Experience cataplexy - losing muscle control suddenly, which makes them collapse
• Have sleep attacks, which is when they fall asleep with no warning
• Have hallucinations or many vivid dreams at night
• Sleep paralysis, which is when they can’t move or speak when trying to wake up

There are different causes of narcolepsy, though it often has a genetic element. Many people with narcolepsy lack a brain chemical called hypocretin, which helps with making us feel awake. People sometimes develop narcolepsy after getting certain infections. 

To learn more about narcolepsy, read this US government fact sheet. To get support, there are several websites and associations with more information. Try More Than Tired, Narcolepsy Network, or My Narcolepsy Team. 

What is epilepsy?

Epilepsy is a condition that makes people have epileptic seizures. This is when a sudden surge in electrical activity in the brain makes their bodies behave in unusual ways. There are many different kinds of epilepsy, but people may experience things like:

• Tonic clonic seizures, where they fall to the ground and shake
• Absence seizures, where they stare blankly into the distance
• Unexpected jerks or twitches
• Seizures during their sleep

To learn more about epilepsy, browse our blog to find out about different syndromes, treatments and tips on living with seizures. 

Sleep: The relationship between sleep and seizures

Misdiagnosis of narcolepsy and epilepsy

While physicians should be able to spot the differences between narcolepsy and epilepsy, they could be mistaken for one another. There are several examples (such as this or this) where misdiagnosis has happened. 

Both people with epilepsy and people with narcolepsy may share similar looking symptoms, including:

• Suddenly falling over

Cataplexy (narcolepsy seizures) may happen when people with narcolepsy feel strong emotions such as laughter or anger. They may suddenly lose muscle tone and fall over. This could look like some kinds of epileptic seizure. 

Related: Other nonepileptic seizures

• Tiredness

People with epilepsy often feel tired - especially if they have seizures at night which disrupt their sleep. Tiredness is also a very common narcolepsy symptom. 

• Non-responsiveness

Both conditions can make people non-responsive. Someone with narcolepsy who is having a sleep attack, for instance, might fall asleep for a few seconds and not respond to questions. This could seem like an absence seizure in epilepsy. 

Although these symptoms could look similar, there are key differences when comparing narcolepsy vs epilepsy:

• Activity on an EEG brain scan

People with epilepsy have very specific forms of electrical activity happening in the brain which can be picked up using an EEG machine. People with narcolepsy don’t have these electrical patterns. 

• Underlying cause

Causes of narcolepsy vary, but it’s often because people don’t have enough of a brain chemical called hypocretin. This isn’t the same for people with epilepsy. 

• Awareness

Most people with epilepsy do not remember their seizures, whereas people with narcolepsy can often remember events such as sleep paralysis or cataplexy. 

Comorbidity - having narcolepsy and epilepsy at the same time

Although narcolepsy and epilepsy are different conditions, people do sometimes have both at the same time (known as ‘comorbidity’). A study in Taiwan found that 8.9% of people with narcolepsy also had epilepsy, which suggests there could be some sort of link between the two. 

Getting the right diagnosis

If you believe you’re experiencing narcolepsy and seizures, then it’s vital to speak to a doctor. They can do tests to work out what’s happening and offer treatment. While there is currently no ‘cure’ for either epilepsy or narcolepsy, there are effective treatments for both which can help manage them and let you live life on your terms.