Narcolepsy

Question 1

HLA association in narcolepsy

Answer 1

HLA-DR2

Question 2

Why do patients with narcolepsy have early onset sleep

Answer 2

• low levels of orexin (hypocretin) which is responsible for controlling appetite and sleep patterns

Question 3

Clinical features

Answer 3

• hypersomnolence
• cataplexy (sudden loss of muscle tone)
• sleep paralysis
• vivid hallucinations

Question 4

Typical age of onset

Answer 4

Teenage years

Question 5

investigation for diagnosis of narcolepsy

Answer 5

multiple sleep latency EEG

Question 6

Management of narcolepsy

Answer 6

daytime stimulants (e.g. modafinil)

night-time sodium oxybate