Internal Medicine

0521779407-14 CUNY1086/Karliner 0 521 77940 7 June 4, 2007 21:17

Narcolepsy 1041

tests

■Diagnosis made clinically

■Routine blood studies are normal.

■Brain imaging is normal.

■Histocompatability antigens (HLA-DR2, HLA-DQw1) are present in

all Japanese & most white pts.

■Sleep studies are abnormal (overnight polysomnogram & multiple

sleep latency tests).

differential diagnosis

■Sleep apnea, restless legs syndrome & psychiatric disorder excluded

by history & by sleep studies (overnight polysomnogram & multiple

sleep latency tests)

■Structural lesions (pituitary adenoma, midbrain glioma, etc) exclu-

ded by brain imaging

management

What to Do First

■Educate pt about the disorder

General measures

■Determine severity

■Determine driving safety: many attacks are predictable & can be

prevented by short daytime naps (15–20 minutes in duration)

■Exercise & caffeinated beverages may prevent attacks

■Avoid heavy meals before period when alertness is required

specific therapy

Indications

■Excessive daytime sleepiness that does not respond to general mea-

sures

➣Modafinil

➣Pemoline

➣Methylphenidate

➣Dextroamphetamine

■Sleep paralysis & cataplexy

➣Tricyclic antidepressants

Protriptyline

Imipramine

Nortriptyline