Published on: 6/20/2025
What tests are used to diagnose narcolepsy?
To diagnose narcolepsy, one common approach doctors often use is a combination of tests. The first test is called polysomnography (PSG), which is an overnight test in a specialized test facility. The morning after the PSG, there is a second test called the Multiple Sleep Latency Test (MSLT), which measures how quickly a person falls asleep in a quiet environment during the day.
Explanation
Narcolepsy is one type of health condition that causes people to feel very sleepy during the day. To find out if someone has narcolepsy, one common approach doctors often use is a combination of tests. The first test is called polysomnography (PSG), which is an overnight test in a specialized test facility. The morning after the PSG, there is a second test called the Multiple Sleep Latency Test (MSLT). The MSLT usually happens about 2-3 hours after the PSG and evaluates how fast a person falls asleep in a calm and quiet place during the day.
How the MSLT Works:
- Multiple Naps: The person takes several naps during the day, usually about five.
- Time to Sleep: The test measures how quickly the person falls asleep during these naps.
Why the MSLT is Important:
- Detects Sleepiness: The MSLT helps doctors see if someone is sleepier than usual.
- Narcolepsy Clues: It can show signs that point to narcolepsy, like falling asleep very fast.
This test is important because it helps doctors figure out if someone has narcolepsy. Remember, tests like the PSG and MSLT are just one part of the process, and doctors may do other tests, too. Other health conditions can also cause a person to feel very sleepy during the day. A healthcare provider will provide personalized medical advice and recommendations.
(References)
- Arand DL, & Bonnet MH. (2019). The multiple sleep latency test. Handbook of clinical neurology, 31277864.
- Folkerts M, Rosenthal L, Roehrs T, Krstevska S, Murlidhar A, Zorick F, et al. (1996). The reliability of the diagnostic features in patients with .... Biological psychiatry, 8830954.
- Aldrich MS, Chervin RD, & Malow BA. (1997). Value of the multiple sleep latency test (MSLT) for .... Sleep, 9351129.
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