[Two cases of photosensitive seizure induced by barcode readers with red flashing lights]

The patient in Case 1 was a 25-year-old female nurse. While she was working at a day-care, she fell down shortly after using a barcode reader. This was followed by a tonic-clonic seizure. The seizure spontaneously stopped after approximately 5 minutes. However, consciousness impairment continued for about 30 minutes. The patient in Case 2 was a 30-year-old female nurse. During the night shift at her workplace, she found it impossible to stand up after staring at the red flashing lights from a barcode reader. The patient was also disoriented, as indicated by her inability to recall her colleague's name. The patient's condition gradually improved and she became fully conscious soon after the episode. We believe that the barcode reader led to photosensitivity in both cases. Barcode readers that emit red flashing lights are thought to have a high potential for triggering photosensitivity. A person is highly likely to display photosensitivity while using the device in a hospital ward. Therefore, special attention is required to avoid photosensitive seizures induced by barcode readers with red flashing lights.