What is the link between seizures and dementia?

There are some symptoms of dementia that are more commonly known, such as memory loss. Seizures are a less common symptom of dementia that are not as understood. Hear from one of our dementia researchers who has been studying seizures in people with the condition.

How common are epileptic seizures in dementia? Who is most at risk of having them? What do these seizures look like? What effect do they have on how someone’s memory changes over time?

These are the questions that I have been researching since starting my PhD in 2016. I'm a student funded by Alzheimer’s Society as part of the University of Exeter doctoral training centre.

What do we know about seizures and dementia?

People with dementia are at risk of having epileptic seizures. We’ve known this for a long time – it was described by Alzheimer himself in 1911.

However, how common they are remains unclear. This is because epileptic seizures can often be subtle. 

There are two common types of epileptic seizures:

Generalised tonic-clonic seizures

Most of us are familiar with the kind of epileptic seizures we see on TV or in films. People become unresponsive, they fall to the ground, become stiff and their whole-body shakes in a convulsion.

Generalised tonic-clonic seizures are hard to miss. But this is not what most epileptic seizures look like. 

Focal onset seizures

Most epileptic seizures in people with dementia are known as focal onset seizures. These can involve brief periods of increased amnesia or unresponsiveness. We see involuntary repeating movements, often of the hands and arms, or of the face (chewing, lip-smacking or swallowing).

Understandably, the latter are more easily missed, especially as the person affected will often quickly be back to normal afterwards.

Who might be affected by seizures?

For a long time, researchers believed epileptic seizures occurred only in people who had long been diagnosed with dementia. It was thought they were a reflection of how much the brain had changed and shrunk because of it. 

However, more recent research has suggested that seizures can occur early-on in Alzheimer’s disease. In some people, seizures may happen even before memory problems become apparent.

As part of my research, I recruited people from the local memory clinic here in Exeter. We asked them questions about epilepsy.

It quickly became clear that most people don’t know that having dementia, particularly Alzheimer’s disease, can increase your risk of seizures.

In our group, around 1 in 8 patients with dementia described episodes which we believe could have been epileptic seizures.

We interviewed our participants one year later and found that those who had described having had epileptic seizures previously performed less well on memory tests than those who showed no evidence of epilepsy. 

Why do people with dementia develop seizures? 

Ultimately, anything that changes the structure of the brain can cause seizures. 

This happens for some people after a stroke, a head injury, or with a brain infection like meningitis. A similar problem is happening in the brain in dementia. As cells in the brain die and the brain shrinks this can lead to epilepsy. 

In addition, we know that two proteins that build up in the brain of people with Alzheimer’s disease – amyloid and tau – affect how the brain’s nerve cells communicate with each other.

Sometimes these nerve cells can become 'hyper-excitable', meaning they can behave uncontrollably, causing epileptic seizures.

Can seizures be managed in people with dementia?

There is good news. There are medicines that are effective at reducing, and hopefully stopping, epileptic seizures.  

If you think that you or someone you know with dementia may be having epileptic seizures, you should tell a doctor. They might want to perform some extra tests and may want to start some extra medicines to treat this problem. 

What we don’t know yet is whether starting treatment for epilepsy might help to slow down dementia and whether it might help keep people’s memory function better for longer.

When is anti-seizure medication typically prescribed?

Anyone can have an epileptic seizure, but most people who have a single seizure will not have any more. As a result, doctors do not usually prescribe anti-seizure medicines in someone after a single seizure.  

While they can be distressing to witness, people who have a seizure typically return to their normal selves soon afterward with no long-term effects. 

However, doctors are likely to look for causes as for why a single seizure may have happened.  

In people with dementia, the fact that they have dementia can be the ‘why’, but other causes should also be considered – including stroke, head injury, and infections.

If someone has a second seizure it suggests they have epilepsy, so starting anti-seizure treatments would be appropriate. Usually this involves a discussion with a neurologist to see which treatment option is most suitable. 

However, telling the difference between single and multiple seizures isn’t always as straightforward as it sounds. For example, if someone has multiple seizures over a few hours (without complete recovery between them) this can still count as a single seizure.  

If someone is having a prolonged seizure (where the person is unresponsive for five minutes or more) it’s likely that doctors would want to administer emergency treatments – usually an injection – to stop the seizure from continuing.

This treatment is important, as seizures can affect someone’s breathing as well as their heartbeat.  

Sometimes people with prolonged seizures may need to be admitted to intensive care to keep them physically stable while they recover.

Why might a person with dementia not be prescribed anti-seizure medication?

If a person living with dementia has a single seizure, doctors may decide not to prescribe an anti-seizure medicine – even though having dementia means the person has a higher risk of having further seizures.

There can be several reasons for this. Some doctors may be concerned that starting an anti-seizure medicine could interfere with other important medicines that the person is already taking.

Others may be concerned that an anti-seizure medicine could cause side effects or make dementia symptoms worse.  

Sometimes, however, starting an anti-seizure medicine may actually help a person’s dementia – at least over the long-term. This is because people who have more seizures in dementia tend to have a faster rate of cognitive decline, so preventing further seizures with medicines may stop this accelerated decline.

Newer anti-seizure medicines are also less likely to interfere with other medications or cause side effects.

This article was first published in 2019 and most recently updated in September 2022.

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194 comments

My father has been getting seizures more and more frequently. He has vascular dementia and has been bedbound since 2018. His doctor initially gave him xanax for anxiety since we didn't know what it was for a while, later on. in 2020, he seems to start to shake and roll his eyes and have a look of being lost or confused. We freak out and the doctor doesn't know what to do anymore. He is on seizure medication. My mother doesn't accept his condition and is hoping he will get better. We have him at home. I keep missing work and i think i am going crazy myself not knowing how to handle all this. I feel like the whole world is falling apart on me. His new seizure med was good for a week, but he went back to his regular convulsions. Any help, advice, or comment to educate me will be helpful. I don't know what to do. The doctor finally gave us a referral to a neurologist next month.

Hi Peter,

We're very sorry to hear this. We'd strongly recommend calling our support line on 0333 150 3456 to speak with one of our trained dementia advisers. They can listen to you, and provide advice and support specific to your situation.

More details about the support line (including opening hours) are available here: https://www.alzheimers.org.uk/dementia-connect-support-line

We hope this helps. Please know that we are here for you.

Alzheimer's Society blog team

There are some good dementia caregiver groups on FB with members who have been dealing with a loved one with dementia for awhile. I found much great advice and support from those groups. Learn all you can, it’s a difficult and scary road but knowing more about it sure helps you deal with it all better. The Alzheimer’s Association is also a good resource.

I was recently diagnosed with temporal lobe epilepsy. Also hippocampal sclerosis.
Have had a feeling of absolute fear wash over like a wave , for many years ( 20 ish years ).
Now getting tonic chlonic seizure .
Have memory loss , worsening!
BLESSED to have VINCE, my partner he is a trained FIRST responder. AM 49 years old. Symptoms as said developed at age of, late 20's
AM COMPLETELY determined to,fight against this.
Also am crazy cat lady . PAGAN/GOTH proud to BE,ME.
BLESSED BE

I had temporal hello Epilepsy for 41 years age 9!to 50. Does Cesarz destroy the left hippocampus and amygdala. The memory portion on the right side doesn’t work so now I can’t even read a page in a book
If I watch a TV show over I won’t remember what I just watched
But the memory deficits have been there for a long time when I was in college when I left I couldn’t remember who my roommates were

Hello Steve,

Sorry to hear that you've been having these memory problems.

We'd strongly recommend calling our support line on 0333 150 3456 to speak with one of our trained dementia advisers. They can listen and learn more about your situation, and provide specific information, advice and support. You can find more details about the support line (including opening hours) here: https://www.alzheimers.org.uk/dementia-connect-support-line

We have some general advice and information about memory loss on our website too, which you may find helpful: https://www.alzheimers.org.uk/about-dementia/symptoms-and-diagnosis/sym…

However, please do call the support line if you need something more specific. They may also be able to suggest other organisations or charities that can support you.

Hope this helps, Steve.

Alzheimer's Society website team

My mother is 77 and has Dementia. Sometimes she freezes up, her body becomes ridged and she looks straight ahead and can’t move or speak. Then she snaps out of it. She has had lots of test and has seen the cardiologist but they haven’t been able to find anything wrong. My suggestions would be appreciated

Thanks for getting in touch, Shirley.

It sounds like you might benefit from talking with other people affected by dementia within our online community, Talking Point: https://www.alzheimers.org.uk/get-support/dementia-talking-point-our-on… It's free to join, and open day or night for carers, family members and people affected by dementia to share their experiences.

We'd also recommend calling our Dementia Connect support line on 0333 150 3456. You can speak with one of our trained dementia advisers about your mother's situation. More details of the support line (including opening hours) are available here: https://www.alzheimers.org.uk/dementia-connect-support-line

We hope this helps for now, Shirley.

Alzheimer's Society blog team

My mother has dementia and they suspect she has begun having seizures. In fact we were just in the ER today due to one. The nurse was asking me if I ever noticed the symptoms you are describing above. You could take her for an EEG to find some answers certainly couldn’t hurt. It’s been heartbreaking watching my mom go through the phases of this disease. I don’t wish this on anyone. My prayers are with you and your precious mother!

Hello, Alzheimer’s Blog Team...
Can you answer a question for me please?
My 86yr old mum is at end stage Alzheimer’s, living in a nursing home since 2016. She had her diagnosis in 2012. For the past 5 yrs she’s been having seizures, related to her dementia. She has myoclonic jerks several times a day but is rarely (only a few times) witnessed to have tonic clonic ones. (Staff are very busy and she’s bed bound in her room). Sometimes she is unrousable or very difficult to wake. I witnessed her have a 10 second fit last week during my visit. She was back to her base line immediately afterwards, without a full postictal phase. This lead me to believe that she may have many more, unwitnessed seizures that the care staff may put down to her being simply “asleep” . Is there any evidence that Alzheimer’s can cause seizures that don’t necessarily have a postictal phase following them? Or that the postictal phase may simply be that she’s sleepy. Or that the frequent jerks that she has are related to her condition? I need to gather as much evidence as I can that she is having more frequent seizures, even though they are un witnessed and therefore not recorded on her notes.
Thank you.

Hello Lesley,

I’m sorry to hear about the difficulties that you and your mum are experiencing, it sounds like you have both been going through a very tough time.

As it sounds like you know, epileptic seizures can take many forms – sometimes these can be generalised tonic-clonic seizures, which are hard to miss. But they can often be far more subtle, or short-lasting, or in some cases ‘sub-clinical’, which means that they have no outward presentation at all.

We also know that the post-ictal period can vary enormously: from hours to even days of increased confusion, drowsiness and agitation, to much shorter lasting periods which may just feature fatigue. So to answer your first question, seizures can occur that don’t always have an obvious post-ictal phase.

We could not confidently say that tonic-clonic seizures can occur without any post-ictal period, but it is certainly possible that these can be subtle, and quite short in duration.

Secondly, I would think it is likely that frequent jerks or myoclonic jerks may be related to her condition. We know that people in the advanced stages of Alzheimer’s disease are prone to developing myoclonic jerks, and that these also appear to be more common in those who experience epileptic seizures.

However, there are also many other causes, and it's important that a doctor checks for these too. This can include abnormal levels of minerals and salts in the blood: such as potassium, sodium, calcium and iron and these can be measured easily with a blood test.

Hopefully, this information can be helpful to you during this time. My best wishes to you and your mother, Lesley.

John

Alzheimer's Society research team

I had a very similar experience with my mother she had 4 seizures in hospital all which I witnessed and had to call to attention of the hospital staff, she was also hard to wake up on one occasion as she looked in a deep sleep but i knew something was wrong and called the staff to awake her, they thought that was a seizure too, they never found anything wrong after many tests the only thing they summarised it might have something to do with low blood pressure in between moving from bed to a chair she was prescribed anti epilepsy medication and hasn't had another seizure since, although it's still very early days I hope this is useful

I had a very similar experience with my mother she had 4 seizures in hospital all which I witnessed and had to call to attention of the hospital staff, she was also hard to wake up on one occasion as she looked in a deep sleep but i knew something was wrong and called the staff to awake her, they thought that was a seizure too, they never found anything wrong after many tests the only thing they summarised it might have something to do with low blood pressure in between moving from bed to a chair she was prescribed anti epilepsy medication I hope this is useful

A couple of years ago my father-in law had an ‘episode’ where he wandered off in the night and didn’t know where he was or where he had been. He had been fine up until then. He has not had anything like it since however, his memory has declined considerably and to me is showing all the signs of dementia. My mother in law is in denial and just believes it’s happened because of this episode. Has anyone else experience anything like this? I’m not sure what advice to give them

Hi JC, thanks for your comment.

We'd recommend calling our Dementia Connect support line on 0333 150 3456. You can talk to one of our trained dementia advisers who will listen to your inlaws' situation and offer you advice and support. More details of the support line (including opening hours) are available here: https://www.alzheimers.org.uk/dementia-connect-support-line

You might also benefit from connecting with other people affected by dementia within our online community, Talking Point: https://www.alzheimers.org.uk/get-support/dementia-talking-point-our-on…

In the meantime, here's some guidance on what to do if you're worried about someone else's memory problems: https://www.alzheimers.org.uk/memoryproblems

And information on walking about, which you may find useful: https://www.alzheimers.org.uk/about-dementia/symptoms-and-diagnosis/wal…

We hope this helps.

Alzheimer's Society blog team

My younger sister aged 63 is in late. stage Altzheimers and suspected Picks disease. She is in a nursing home and cannot do anything for herself. Last Saturday she had a seizure for the first time, where she was staring eyes open, fixed posture, mouth open and completely unresponsive for about an hour and a half. The paramedics said all her vital signs were fine, and it was agreed not to take her into hospital and best left looked after in bed. When she came round she behaved as though nothing had happened, and was clapping and strange singing type sounds as she often makes. The GP is going to do blood and urine tests to check for any underlying infection, and possibly give her seizure medication. Other than that, family and medical staff agree that she is best left comfortable and monitored in the home. I had no idea about the link between seizures and dementia until I just saw this article even though both our father and his mother had Altzheimers. It’s such a cruel disease, and all the children from my sister and myself and their children are concerned about the risk of dementia for themselves in case it is genetically in the family.

My mum was admitted to hospital on the 12th June after taking a seizure, she had a ct scan done and we were told that she was in the early stages of dementia. Her father had Alzheimer’s so it was something I kind of expected but never wanted to actually happen. On Saturday she was admitted to hospital yet again after taking another seizure, this one lasted for almost three minutes and took most of the day before she started to respond to me in the hospital. The doctors said she also had taken another one on the way to the hospital but it only lasted seven seconds. Mum also is a carrier of a condition called Leber Hereditary optic neuropathy, my nephew was diagnosed with it two years ago and is losing his eyesight. Mums great grandson has also been diagnosed with the same condition and he’s only four. I know very little about Alzheimer’s but with everything else mum has going on I am so worried about her, she’s in a nursing home which means as she was in hospital at the weekend she now has to isolate in the home for fourteen days which is breaking my heart.

I am 37 years old and have epilepsy. I recently started noticing me forgetting certain things that happen during the day and also seem to forget where I’m at sometimes and my purpose for being there. It’s only happened a few times recently but definitely something that has worried me. I’m assuming it’s from my past seizures but I am really trying to get some answers. Anyone with the Same type of experiences?

My daughter had epilepsy and very bad migraine when She was 9 years old until 16, She was taken the maximum dose of medicine the Drs could give, and because one of the meds side effects was temporary memory lost, but She is 23 years old, she Was able to stop meds but her memory still doesn’t come back normal completely, she forgets things and she will remember 2 o 3 days later, she needs to write everything.

I’m 39 with epilepsy and a lesion on my left frontal lobe from a TBI from a car accident as a kid and I don’t think the other two from when I was older helped. I’m forgetting so much more now including the day, and date of the week. I’m unable to keep seizures under control no matter what medication levels are tried either. Hugs!! I understand the fear.

My dad (78) has recently started having seizure like episodes, completely out of the blue. He has not been diagnosed with dementia / Alzheimer’s although he has been referred for this as the signs are becoming more and more apparent however the doctors seem quite dismissive over the fact that it is not related at all. The only person who has said it could be related is the A&E manager who was on duty the night my dad was taken into hospital following one of these seizures. Any help or advice would be gratefully received. My dad is extremely depressed now as he has gone from being a very fit man with his independence to now relying on other people for lifts to places etc…. and to also have his exercise options limited. Myself coming from an NHS background, I am becoming increasingly frustrated at the lack of diagnosis for my dad.

Hello Claire,

Thanks for your comment, and really sorry to hear about this experience with your dad.

We'd always recommend speaking to your doctor first if you're worried about memory problems, so it's great that you've done that already.

If this has left you frustrated, then you can also speak to one of our dementia advisers for more advice about assessments and diagnosis. To do this, just call our Dementia Connect support line on 0333 150 3456.

The support line is open seven days a week:

9.00am to 8.00pm Monday, Tuesday and Wednesday
9.00am to 5.00pm Thursday and Friday
10.00am to 4.00pm Saturday and Sunday.

Hope this helps, Claire.

Alzheimer's Society blog team

My mom was 67 when she died from dementia. She had frequent seizures and brain shrinkage.

I am dealing with now at 52 years of age and doing my best to remain hopeful and optionsitc,but it's down right hard at times. I do my best to take the resolve it's never in life what occurs but how we respond to it emotionally.

Hello Kelly

We would strongly recommend speaking with one of our dementia advisers by calling the Dementia Connect support line on 0333 150 3456. This is a great way to get dementia information, advice and also emotional support. (More information about the support line, including opening times, can be found here: https://www.alzheimers.org.uk/dementia-connect-support-line)

You may also benefit from talking with other people affected by dementia within our online community, Talking Point. Feel free to browse and read others' experiences, or create an account to reply and connect with others. You may find more similar situations to yours there: https://forum.alzheimers.org.uk/

Hope this is helpful for you, Kelly. Please don't hesitate to call our support line any time you need advice or someone to talk to.

Alzheimer's Society blog team

My mom is 70 years old and experienced what we now know to be absence seizures. At first she was diagnosed with epilepsy about five years ago but in the past year after uncontrolled seizures through all of this time despite trying several combinations of seizure medications (including Kepra, Donepezil, Lamotragine, Briviact and now a newer trial drug XCopri) she has finally been diagnosed with Alzheimer's disease which I suspected and had been questioning doctor's all along. Her seizures are just like many here have described, blank staring, shaky, body going limp or frozen, some light shaking. Afterwards her memory is terrible and she often loses short term memory from the day before and after. Her seizures have increased drastically in frequency and no doctors have been able to pinpoint what has caused this or been able to control it. Her memory in the last few months has gone from mixing up her grandchildren's names to not even recognizing them. This is an awful disease but this rate is terrifying and I don't know where else to look for help. Would love anyone's suggestions, input or personal experiences. Thank you for your time.

My mum was diagnosed Alzheimers at the beginning of the year but knew something wasn't right a long time before. Mum has been having seizures for a couple of years, her whole body goes stiff and her eyes stare, she doesn't shake. She says she feels like she is falling. Up until reading this article I didn't make the connection. Mums doctors just say they don't know what causes her condition. This has been helpful.

Thank you for this article, it most helpful. For over 14 mths I have been advising the Dr that my husband's focal seizures are followed by confusion & memory loss. Both the neurologist & Dr have dismissed these concerns. This article gives me something tangible to share with them.

My husband age 77 has had vascular dementia for 8 years , he has seizures that last several hours , he was hospitalised for ten days and given tests, the hospital refers to them as episodes and tell me these will continue and not to bother calling 999 in future but he is unresponsive during these episodes , one day it lasted for six hours can anyone tell me if this is normal for him

Hello Suzanne,

Thanks for your comment. These episodes must be concerning. Seizures and dementia is a complex area, so we'd really recommend that you and your husband speak to the GP.

For dementia information, advice and support, you can speak to our dementia advisers through our Dementia Connect support line on 0333 150 3456. They're available seven days a week: https://www.alzheimers.org.uk/dementia-connect-support-line

Some people also find it helps to talk with others who have gone through or are going through similar experiences. If you think this would help, you can visit our online community, Talking Point, for peer support: https://forum.alzheimers.org.uk/ It's free and open day or night.

Hope this helps for now, Suzanne.

Alzheimer's Society blog team