Sleep testing with polysomnography (PSG) and a multiple sleep latency test (MSLT) is usually needed for a diagnosis.

Getting these 2 tests is generally necessary for an accurate diagnosis of narcolepsy. Your sleep specialist will have you stay overnight at a sleep laboratory to conduct these 2 tests. You will be given a private room with a video/audio system so you can communicate with the technologists outside your room.

Please note that home sleep apnea tests (HSATs or HSTs) are used to diagnose obstructive sleep apnea (OSA) in people with suspected moderate to severe OSA. HSATs/HSTs do not screen for narcolepsy.


PSG is performed during the overnight part of your stay at the sleep laboratory. Sensors will be placed on your scalp, chest, and legs. As you sleep, a computer records your brain waves, blood oxygen level, heart rate, breathing, and eye and leg movements.


The MSLT starts the morning after PSG and measures how quickly you fall asleep during the day and monitors how quickly and how often you enter rapid eye movement (REM) sleep. You will be asked to nap in 20-minute sessions every 2 hours throughout the day. Brain activity and oxygen levels continue to be monitored.


According to the American Academy of Sleep Medicine, overnight PSG followed by an MSLT should be performed in children whose doctors suspect they may have narcolepsy. How long your child is asked to sleep during the PSG may be different than for adults because how much sleep someone needs varies with age.

The MSLT may be difficult to perform in children, and guidelines for what are considered normal test results for very young children have not been established. However, overnight PSG followed by MSLT is considered standard testing for children with suspected narcolepsy.