Type 1 narcolepsy, also known as narcolepsy with cataplexy and narcolepsy-cataplexy, is a neurological disorder. In people with type 1 narcolepsy, the brain does not regulate sleep properly. People with narcolepsy experience parts of the sleep cycle randomly, at the wrong times, throughout the day.

Type 1 narcolepsy (previously known as narcolepsy with cataplexy)—This diagnosis is based on the individual either having low levels of a brain hormone (hypocretin) or reporting cataplexy and having excessive daytime sleepiness on a special nap test.

Narcolepsy type 1 (NT1) can be clinically characterized by symptoms of EDS and cataplexy, and/or will have CSF orexin levels of less than 110 pg/ml. Cataplexy are transient episodes of aberrant tone, most typically loss of tone, that can be associated with strong emotion.

This can be triggered by strong emotion, especially laughter. Narcolepsy is divided into two types. Most people with type 1 narcolepsy have cataplexy. Most people who don't have cataplexy have type 2 narcolepsy. Narcolepsy is a life-long condition for which there's no cure.