Narcolepsy is a condition characterized by excessive daytime sleepiness and symptoms that represent intrusion of REM sleep into waking hours. It is caused by a deficiency of the neurotransmitter hypocretin and is associated with HLA DQB1*0602. Symptoms include irresistible sleep attacks, cataplexy, sleep paralysis, and hypnagogic hallucinations. Diagnosis involves evaluating symptoms, sleep latency on polysomnography and multiple sleep latency tests, and hypocretin levels in cerebrospinal fluid. Treatment focuses on managing symptoms with stimulants like modafinil and antidepressants or SSRIs to reduce cataplexy.

1. BY: DR. ABHISEK CHOUDHURY
(INTERN)
MENTOR: DR. LAVANYA SETH
DEPT. OF PSYCHIATRY
NARCOLEPSY

2. CONTENTS
• INTRODUCTION
• SYMPTOMS
• INCIDENCE
• PATHOLOGY
• DIAGNOSTIC CRITERIA
• TREATMENT
• SUMMARY

3. INTRODUCTION
• Narcolepsy is a condition characterized by excessive sleepiness,as well
as auxillary symptoms that represent intrusion of aspects of REM
sleep into the waking state.
• The sleep attacks of narcolepsy represent episodes of irresistible
sleepiness,leading to perhaps 10 to 20 minutes of sleep,after which the
patient feels refreshed,at least briefly.
• They can occur at inappropriate times(e.g.,while eating,talking, or
driving).
• This disorder can be dangerous because it can lead to automobile &
industrial accidents.

4. SYMPTOMS
• Cataplexy involves sudden loss of muscle tone,usually with continuing
full or partial consciousness.
• Cataplexy can be recognized by “spontaneous grimaces or jaw –
opening episodes with tongue thrusting or a global hypotonia,without
any obvious emotional triggers.”
• Sleep paralysis & hypnagogic (or hypnopompic) hallucinations are
nonspecific symptoms & may occur in isolation or in conjunction with
other sleep disorders.

7. INCIDENCE
• Narcolepsy is estimated to occur in 0.02 to 0.16 % adults & shows
some familial incidence.
• It is neither a type of epilepsy nor a psychogenic disturbance.
• It is an abnormality of the sleep mechanisms especially ,REM-
inhibiting mechanisms & has been studied in dogs,sheep & humans.
• It can occur at any age ,but most frequently begins in adolescence or
young adulthood, generally before the age of 30.
• The disorder either progresses slowly or reaches a plateau that is
maintained throughout life

8. PATHOLOGY
• It is an immune mediated disorder.
• Occurs due to deficiency of hypocretin.
• Hypocretin promote alertness & appetite.
• Hypocretin neurons projects from hypothalamus.
• Strong association with human leucocyte antigen class II (HLA
DQB1*0602)

10. ICD-10 CRITERIA
• Code for Narcolepsy is G47.4
• DIFFERENTIAL DIAGNOSIS: Hypersomnia
NARCOLEPSY HYPERSOMNIA
a. One or more auxillary symptoms present. a. No such specific symptoms.
b. Sleep attacks are irrestible & more refreshing. b. Sleep attacks usually fewer per day,each of longer
duration,patient is able to prevent their occurrence.
c. Nocturnal sleep is fragmented & curtailed. d. Nocturnal sleep is prolonged ;marked difficulty in
achieving fully aroused state upon awakening.

11. ICD-11 CRITERIA
• Narcolepsy, Type 1 (7A20.0)
• Narcolepsy, Type 2 (7A20.1)
• Narcolepsy, unspecified (7A20.Z)

12. DSM-5 DIAGNOSTIC CRITERIA FOR
NARCOLEPSY:
A. EDS at least 3 times per week over the past 3 months.
B. Presence of at least 1 of the following:
1. Episodes of cataplexy, defined as either (a) or (b):
a. In individuals with long-standing disease, brief (seconds to
minutes) episodes of sudden bilateral loss of muscle tone with
maintained consciousness that are precipitated by laughter or joking.
b. In children or in individuals within 6 months of onset,
spontaneous grimaces or jaw-opening episodes with tongue
thrusting or a global hypotonia, without any obvious emotional
triggers.

13. 2. Low CSF levels of hypocretin-1 must not be observed in the
context of acute brain injury, inflammation, or infection.
3. Nocturnal PSG showing REM sleep latency≤ 15 min, or MSLT
showing a mean sleep latency ≤ 8 min and 2 or more sleep-onset REM
periods.

15. TREATMENT
• No cure available, only symptomatic management.
• Modafinil (DOC)
• Trycyclic drugs or SSRIs to reduce cataplexy.
• Take forced naps.
• Advise patient not to do any dangerous activity like driving &
swimming as he might sleep in between & can harm himself/herself.

16. SUMMARY
• Narcolepsy is a condition characterized by excessive sleepiness.
• Characterized by tetrad of symptoms. These included (1) excessive
sleepiness,(2) cataplexy,(3)sleep paralysis,and (4)hypnagogic
hallucinations.
• Reduced latency of REM Sleep.
• Symptomatic treatment available.
• Modafinil is the drug of choice.

17. BIBLIOGRAPHY
• KAPLAN & SADOCK’S COMPREHENSIVE TEXTBOOK OF
PSYCHIATRY,10th Ed.
• KAPLAN & SADOCK’S SYNOPSIS OF PSYCHIATRY,11th Ed.
• ICD 10 & ICD 11