What Is Photosensitive Epilepsy?
Reviewed by: HU Medical Review Board | Last updated: May 2022
Photosensitive epilepsy is a type of reflex epilepsy. Reflex epilepsies are a group of syndromes that have specific triggers that cause seizures.1
Photosensitive epilepsy is when seizures are triggered by things that you see. These things can include flashing lights or patterns. Photosensitive epilepsy can be difficult to manage because everyday things can be triggers. Sunlight reflecting off water or the flicker of a TV screen are common triggers.2
For some people, simply avoiding triggers can be enough to prevent seizures. But other people may need anti-seizure drugs to control their seizures. Despite the challenges, many people with photosensitive epilepsy are able to live happy and fulfilling lives.2
About 3 in 100 people with epilepsy have photosensitive epilepsy.3
What can trigger photosensitive epilepsy?
Triggers vary from person to person, but some examples include:2
- Bright strobing lights, like the lights that flash on visual fire alarms
- Sunlight, especially:
- On water
- Flickering through trees
- Shining through blinds
- Stripes or contrasting colors
- Rapid flashing from video games or TV shows
Things that might increase your risk
Some situations might make it more likely for you to have a seizure if you have photosensitive epilepsy. Everyone is different, but these things include:3
- Prolonged screen time, like playing a video game for a long time
- High-contrast images, like watching a movie in a dark room
- An image taking up your entire field of view, like sitting too close to a screen
Symptoms of photosensitive epilepsy
Photosensitive epilepsy usually causes generalized tonic-clonic or focal seizures:2,4,5
- Tonic-clonic seizures (previously "grand mal" seizures) cause:
- Muscle stiffening
- Loss of consciousness
- Violent jerking
- Focal seizures come from a single area of the brain. Symptoms vary depending on where in the brain the seizure occurs. Depending on the type, you can be awake or confused if you have a focal seizure.
Many people get headaches or respond negatively to certain light triggers, but do not have seizures. This is not epilepsy.2
First, talk to your doctor about your sensitivity to light. What are your triggers? Does anything make it better or worse? Your doctor will want to know your medical history, including everything that happened before your seizures.2
Your doctor will order an EEG, or electroencephalogram. An EEG is a painless test that records your brain's electrical activity. During the test, electrodes are attached to your scalp, and strobing lights will be positioned in front of your eyes. Your doctor will look at your brain's electrical activity to see if you have seizures in response to the light.2
Managing your epilepsy
If you have photosensitive epilepsy, there are some things you can do to help manage it:2
- Wear sunglasses when outdoors or exposed to bright lights.
- Avoid flashing lights when possible.
- Watch TV in a well-lit room and sit as far back from the screen as possible.
- Set a timer to avoid too much screen time.
- Wear polarized sunglasses when watching TV.
- Reduce the TV brightness when playing video games.
- Cover 1 eye when playing video games. Switch which eye is covered.
- Take frequent breaks from screens and video games.
- Wear non-glare glasses or glasses that block blue light when working at a computer.
- Install a glare guard on your computer monitor.
You may find it impossible to completely avoid triggers. Driving at certain times of the day can produce shadows that mimic strobe lights and induce seizures. Because of this, many people have to manage their condition with antiseizure drugs.2
What if I am exposed to a trigger?
Covering 1 eye instead of closing both eyes or turning away from the trigger might help. Talk to your doctor about if it is safe for you to drive and whether you need to take other precautions. With planning and other treatments, you can live a productive life with photosensitive epilepsy.2,3