Functional (dissociative) seizures

What are functional (dissociative) seizures?

Functional (dissociative) seizures are when people lose control of their body. They may shake or black out. Some people do both.

These types of seizures look and feel like epileptic seizures. But they happen for a different reason.

Functional (dissociative) seizures are a type of functional neurological disorder (FND). The seizures happen because there is a functional problem with the brain, not a structural one.

NHS Scotland describes the brain as a computer. In FND, there’s no damage to the hardware, or structure, of the brain. It’s the software, or program running on the computer, that isn’t working properly.

Functional (dissociative) seizures do not cause damage to the brain, even if they go on for several minutes.

How common are functional (dissociative) seizures?

Between 2 and 33 in every 100,000 people have functional (dissociative) seizures. They are not as common as epilepsy.

One small study found that 11 in every 100 (11%) people taken to hospital for seizures are thought to have functional (dissociative) seizures.

Other names for functional (dissociative) seizures

There are lots of different names for functional (dissociative) seizures. Doctors do not always agree on what to call them. Commonly used names include:

• Non-epileptic attack disorder (NEAD)
• Non-epileptic seizures
• Psychogenic non-epileptic seizures (PNES)
• Psychogenic seizures

Functional (dissociative) seizures used to be called ‘pseudoseizures’. This term is not used anymore because it suggests that these seizures are made up or ‘put on’.

This is not true. Functional (dissociative) seizures are real, physical symptoms that need medical treatment.

Symptoms of functional (dissociative) seizures

Functional (dissociative) seizures can look like epileptic seizures. The symptoms can include:

• Uncontrolled shaking
• Suddenly going motionless and unresponsive
• Staring without responding to surroundings

Some people are aware that these seizures are going to happen. For others, they happen without warning. This type of seizure can often go on for longer than 5 minutes and can be confused with status epilepticus.

Functional (dissociative) seizures may not always follow a predictable pattern. They can vary in:

• How often they happen
• How long they last
• How severe they are

What causes functional (dissociative) seizures?

It can be difficult to understand what causes functional (dissociative) seizures. They happen for different reasons in everyone. But there are some things that make functional (dissociative) seizures more likely.

The biggest cause of functional (dissociative) seizures is trauma. This can include childhood trauma, such as sexual, physical or mental abuse.

Stressful life events such as illness or bereavement can also cause this type of seizure.

Some people who develop functional (dissociative) seizures have post-traumatic stress disorder. Other risk factors may include:

• Personality disorder
• Depression and anxiety
• Chronic pain
• Sleep problems
• Migraine
• History of neurodivergence, such as ADHD or autism
• History of accident or head injury

But not everyone with functional (dissociative) seizures will have experienced trauma or stress. The seizures can also appear without any clear trigger.

People with learning disabilities may also have an increased risk of having functional (dissociative) seizures. This risk increases if they have epilepsy as well.

How are dissociative seizures diagnosed?

Call 999 if someone is having a suspected seizure for the first time.

You should see your GP as soon as possible if you, or someone you care for, has had a suspected seizure and you did not go to the hospital at the time. Anyone who has had a suspected seizure should have an ECG (electrocardiogram). This is to exclude a heart problem. You will likely have other tests too.

Your doctor may suspect epilepsy first. Find out more about diagnosing epilepsy.

It is important to have a detailed description of what happens during a seizure.

Research shows that video-EEG monitoring is the most reliable way of diagnosing functional (dissociative) seizures.

Video EEG is where you’re filmed while an EEG recording is taken. This can help provide more information about your brain activity.

The test is usually carried out as an outpatient over about 30 minutes. If you do not have any typical seizures during the test, the test may need to be carried out over a few days. This can be done at home or while staying in a purpose-built hospital suite.

Filming your seizures

This may not feel like a natural thing to do. But showing video clips of a seizure to a doctor or nurse can be a very helpful way of getting the right diagnosis.

If possible, ask someone to film you during a seizure on their phone.

If you have been asked to film someone, make sure the person having a seizure is safe before you start filming. Move anything that could hurt them out of the way first and note the time the seizure started.

It may also be useful to keep a seizure diary before your appointments.

Functional (dissociative) seizures and epilepsy

People with functional (dissociative) seizures can be misdiagnosed with epilepsy first. Some people with epilepsy are misdiagnosed with functional (dissociative) seizures first. This is less common.

Some people with functional (dissociative) seizures are treated with epilepsy medicine for several years before the correct diagnosis is made.

This does not necessarily mean that you’ve had bad doctors. Sometimes the diagnosis becomes clearer over time, when more seizures have been observed.

Epileptic seizures can be harmful. So doctors may prescribe epilepsy medicine if they think you have the condition.

It is not uncommon to have epilepsy and functional (dissociative) seizures at the same time. One study estimates that 22 in 100 people with functional (dissociative) seizures also have epilepsy.

What is the treatment for functional (dissociative) seizures?

Medicine

There is no specific medicine available to treat functional (dissociative) seizures. Your doctor may talk to you about taking antidepressants if you are having these types of seizures and have:

• Depression
• Anxiety
• Panic attacks

Talking therapies

Talking therapies may help you understand how and why your seizures are happening.

There are different types of talking therapy. These include counselling and cognitive behavioral therapy.

Your doctor may offer you an appointment with a trained mental health specialist. This may be a psychologist, psychotherapist or counsellor.

Epilepsy medicines and functional (dissociative) seizures

There is no evidence that epilepsy medicine can treat functional (dissociative) seizures.

Unless you have epilepsy, your specialist will help you to reduce and stop taking epilepsy medicine safely.

Accepting a diagnosis of functional (dissociative) seizures

Some people find it difficult to accept a diagnosis of functional (dissociative) seizures. This can be for many reasons, such as:

• They find it hard to understand how physical symptoms can happen without a structural cause or abnormality on investigations
• They don’t remember or don’t understand what is triggering the attacks
• They are worried that they are ‘crazy’ or that other people will think they are

These are all understandable feelings. But it is important not to let these feelings stop you from getting treatment.

Functional (dissociative) seizures are real. And talking therapies are an effective medical treatment that can help you manage your condition.

What can I do to help myself?

There are things you can do that may help you manage your condition. This includes:

• Relaxation techniques
• Learning to understand what triggers your seizures
• Staying connected to friends and family you love and trust

Sheffield Teaching Hospitals NHS Foundation Trust has a leaflet full of tips and advice that may help you.

Will I get better if I have functional (dissociative) seizures?

Some people get better and others need more support to manage their symptoms.

It’s likely that your symptoms will come and go and change over time. They may in increase during stressful times.

It may be more helpful to focus on finding effective ways to manage your symptoms, rather than thinking about if the seizures will go away

What is the first aid for functional (dissociative) seizures?

Dissociative (functional) seizures do not cause damage to the brain, even if they last a long time.

If someone is having a functional (dissociative) seizure you should:

• Protect them from injury (remove harmful objects from nearby)
• Cushion their head
• Help their breathing by gently placing them in the recovery position once the seizure has stopped
• Stay with the them until they are fully recovered
• Be calm and reassuring

Do not:

• Hold them down or restrain them
• Put anything in their mouth

Should I call an ambulance?

You do not usually need to call an ambulance if someone you know is having a functional (dissociative) seizure.

But do call 999 if:

• It is someone’s first seizure
• If you do not know what type of seizure it is
• They are having repeated seizures
• The seizure continues for more than 5 minutes
• The person is unresponsive for more than 10 minutes after the seizure
• They are injured or they are not breathing normally

Can I drive if I have functional (dissociative) seizures?

You must not drive if you have been diagnosed with functional (dissociative) seizures. You must tell the DVLA about your diagnosis. This rule applies to cars, motorcycles busses and lorries. 

You may get your licence back after 3 months if you stay seizure free.

The DVLA may ask for a specialist’s review before reissuing your licence if your seizures are likely to happen while you are driving.

You will need to follow the driving rules for epilepsy if you have epilepsy as well.

Where can I get more information and support?

FND Action 

FND Action is a registered charity for people with functional neurological disorder. 

FND Guide 

This website explains the symptoms of functional (dissociative) seizures and FND, written by a neurologist and colleagues. 

FND Hope UK 

FND Hope UK is a registered charity for people with functional neurological disorder. 

FNDMattersNI 

FNDMattersNI is a registered charity in Northern Ireland. They provide support to people with functional neurological disorder.  

Neurokid  

Website for children and young people with dissociative seizures.  

Non-Epileptic Attacks 

This website created by a group of healthcare professionals who work or have worked at the Sheffield Teaching Hospitals NHS Foundation Trust supporting people with non-epileptic attacks (functional seizures).  

Sheffield Teaching Hospitals NHS Foundation Trust

This trust has more information about functional seizures (non-epileptic arrack disorder (NEAD)