The relationship between seizures and strokes

17th January 2019

As you may already be aware, there is a common link between seizures and strokes. Both affect the brain and can influence emotions, mobility, communication, memory and behaviour in a person. This can make it much more difficult to recognise seizures in a person who has had a stroke.

It’s also true that seizures can be more common post-stroke, with 22% of people who have had a stroke also having seizures afterwards. It’s important to watch closely for seizure activity in a person who has had a stroke as it can be subtle differences that are more difficult to recognise.

Why do strokes increase risk of seizures?

A stroke can cause various types of injury to the brain, and as with exterior injuries, this can leave a scar. It’s these post-stroke scars that can cause disturbances in the electrical activity of the brain. Rather than the regular on and off patterns of the brain cells, random bursts of energy can cause unintentional movements, sensations and even render the person unconscious. It’s this damage that often leads to a person being more susceptible to seizure activity than they were pre-stroke.

Which type of stroke is the most likely to cause seizures?

There are two types of stroke, known as hemorrhagic or ischemic. The key difference between these two types of stroke is that hemorrhagic is the result of a weakened blood vessel rupturing and bleeding into the brain. An ischemic stroke on the other hand is caused due to an obstruction within the blood vessel, which reduces the supply of oxygen to the brain.

Those who have suffered from a hemorrhagic stroke are far more likely to experience a seizure afterwards. The likelihood of seizures is also increased if the stroke occurs in the cerebral cortex area of the brain, which is the outer layer of tissue.

Does this mean epilepsy?

Having a seizure does not necessarily mean that a person has epilepsy. A single seizure is rarely enough for a diagnosis of epilepsy. However, if the person experiences two or more seizures post-stroke this may indicate that they have developed epilepsy. It’s less common for a person who has had a stroke to fully develop epilepsy, however, it is entirely possible.


If you have experienced a seizure as an isolated incident, it’s highly unlikely that you will receive treatment. However, if you are diagnosed with epilepsy, this will often mean being prescribed anti-epileptic drugs (AEDs).

AEDs work by inhibiting the bursts of energy in the brain that cause a person to have seizures. 70% of the seizure population will become seizure free with the most appropriate anticonvulsant therapy .

National Epilepsy Training can help

For more information on the relationship between strokes and seizures, or to enquire about our training and care services, please call us on 01706 373075 or email