Triggers

Triggers

Triggers are situations that can bring on a seizure in some people with epilepsy. Some people do not have any specific triggers for their seizures, but common triggers include tiredness and lack of sleep, stress, alcohol, and not taking medication. For some people, if they know what triggers their seizures, they may be able to avoid these triggers and so lessen the chances of having a seizure.

For some people, seizures can be triggered by flashing or flickering lights or patterns. This is called photosensitive epilepsy. Photosensitive epilepsy affects only up to 5% of people with epilepsy, and it is standard to be tested for photosensitive epilepsy when you go through a diagnosis of epilepsy. The test involves looking at  sequences of light flashes during an EEG so that the doctors can see if your brain activity on the EEG recording changes when you are exposed to the light stimulation. If you are not sure whether you may be photosensitive, you can ask your GP or specialist whether you’ve had the test for it.

Triggers for seizures are not the same as causes for epilepsy. A trigger for someone to have their first seizure may be a stressful situation, but the underlying cause for that person to start having seizures may be quite different.  Causes can include structural damage to the brain, from birth, from a stroke, or an infection such as meningitis, or through a head injury. Causes can also be genetic, for example a naturally low resistance to having seizures (a low seizure threshold), or another condition that makes a person more likely to develop seizures, such as Tuberous Sclerosis.

Because epilepsy can develop at any time of life, it can sometimes be difficult to work out why seizures have started. If you have a seizure, it may seem to make sense that there must be a particular cause, such as stress, or alcohol, for example. However, the likelihood of having a seizure at some point may have been there already for you, and the stress or alcohol has triggered it.

© Epilepsy Society.

Information produced in October 2012.