Disney has issued a warning that visuals and sustained flashing light sequences in “Star Wars: The Rise of Skywalker” could affect those with photosensitive epilepsy.

The studio is working with the Epilepsy Foundation, which also issued a warning on Friday about the potential health risk.

“Out of an abundance of caution, we recommend that you provide at your venue box office and online, and at other appropriate places where your customers will see it, a notice containing the following information: ‘Star Wars: The Rise of Skywalker’ contains several sequences with imagery and sustained flashing lights that may affect those who are susceptible to photosensitive epilepsy or have other photosensitivities,” Disney said in a letter to exhibitors.

The foundation thanked Disney for its efforts in advance of the movie’s release on Dec. 20. It noted that for about 3% of people with epilepsy, exposure to flashing lights at certain intensities or certain visual patterns can trigger seizures. “This condition is known as photosensitive epilepsy and it’s more common in children and adolescents,” the foundation said.

“If you or someone you know are sensitive to lights, please consider the following as you make plans to watch the movie: Ask a friend to watch the movie first; Take your friend with you when you go see the film to alert you to which scenes contain the flashing lights so you block your eyes during those scenes; Teach your friend the three simple steps of seizure first aid — Stay, Safe, Side — so that they can assist if you have a seizure,” the foundation said.