Narcolepsy

What is Narcolepsy

Narcolepsy is a neurological disorder that causes you to fall asleep suddenly, and without control, during the daytime (sleep attacks). Narcolepsy is a lifelong (chronic) disorder.

Normally, sleep follows a regular cycle over the course of the night. After about 90 minutes of light sleep, your sleep should become deeper. When your sleep becomes deeper, your body moves less and you start dreaming.

This type of deep sleep is called rapid eye movement (REM) sleep. When you have narcolepsy, your REM sleep is not well-regulated. This disrupts your sleep cycle, which causes daytime sleepiness.

6 Interesting Facts of Narcolepsy

1. Narcolepsy is an incurable sleep disorder characterized by excessive daytime sleepiness that may be associated with cataplexy, hypnagogic hallucination, or sleep paralysis
2. Diagnostic criteria include:
   • Clinical manifestation of cataplexy and daily excessive sleepiness lasting longer than 3 months 
   • Multiple sleep latency test showing sleep latency of 8 minutes or less and 2 or more periods of sleep-onset rapid eye movement 
   • Cerebral spinal fluid orexin A level of 110 pg/mL or less 
3. Treatment of excessive daytime sleepiness includes improved sleep hygiene and use of short 15-minute naps during the day; most patients will require the addition of central nervous system stimulants (eg, modafinil, methylphenidate, amphetamines) or sodium oxybate (γ-aminobutyric acid receptor agonist)
4. Treatment of cataplexy includes antidepressants (eg, venlafaxine, fluoxetine, clomipramine) or sodium oxybate
5. Antidepressants also used to suppress severe hypnagogic hallucinations and sleep paralysis
6. There is no cure for narcolepsy; however, symptoms can be improved with drug therapy and good sleep hygiene

What are the causes?

The cause of narcolepsy is not fully understood, but it may be related to:

• Low levels of hypocretin, a chemical (neurotransmitter) in the brain that controls sleep and wake cycles. Hypocretin imbalance may be caused by:
  • Abnormal genes that are passed from parent to child (inherited).
  • The body’s defense system (immune system) attacking hypocretin brain cells (autoimmune disease).
• Infection, tumor, or injury in the area of the brain that controls sleep.
• Exposure to poisons (toxins), such as heavy metals, pesticides, and secondhand smoke.

What are the symptoms?

Symptoms of this condition include:

• Excessive daytime sleepiness. This is the most common symptom and is usually the first symptom you will notice. This may affect your performance at work or school.
• Sleep attacks. This means falling asleep suddenly and without control. You may fall asleep in the middle of an activity, especially low-energy activities like reading or watching TV.
• Feeling like you cannot think clearly.
• Trouble focusing or remembering things.
• Feeling depressed.
• Sudden muscle weakness (cataplexy). When this occurs, your speech may become slurred, or your knees may buckle. Cataplexy is usually triggered by surprise, anger, fear, or laughter.
• Loss of the ability to speak or move (sleep paralysis). This may occur just as you start to fall asleep or wake up. You will be aware of the paralysis. It usually lasts for just a few seconds or minutes.
• Seeing, hearing, tasting, smelling, or feeling things that are not real (hallucinations). Hallucinations may occur with sleep paralysis. They can happen when you are falling asleep, waking up, or dozing.
• Trouble staying asleep at night (insomnia).
• Restless sleep.

How is this diagnosed?

This condition may be diagnosed based on:

• A physical exam to rule out any other problems that may be causing your symptoms. You may be asked to write down your sleeping patterns for several weeks in a sleep diary. This will help your health care provider make a diagnosis.
• Sleep studies that measure how well your REM sleep is regulated. These tests also measure your heart rate, breathing, movement, and brain waves. These tests include:
  • An overnight sleep study (polysomnogram).
  • A daytime sleep study that is done while you take several naps during the day (multiple sleep latency test, MSLT). This test measures how quickly you fall asleep and how quickly you enter REM sleep.
• Removal of spinal fluid to measure hypocretin levels.

How is this treated?

There is no cure for this condition, but treatment can help relieve symptoms. Treatment may include:

• Lifestyle and sleeping strategies to help you cope with the condition, such as:
  • Exercising regularly.
  • Maintaining a regular sleep schedule.
  • Avoiding caffeine and large meals before bed.
• Medicines. These may include:
  • Medicines that help keep you awake and alert (stimulants) to fight daytime sleepiness.
  • Medicines that treat depression (antidepressants). These may be used to treat cataplexy.
  • Sodium oxybate. This is a strong medicine to help you relax (sedative) that you may take at night. It can help control daytime sleepiness and cataplexy.

Follow these instructions at home:

Sleeping habits

• Get about 8 hours of sleep every night.
• Go to sleep and get up at about the same time every day.
• Keep your bedroom dark, quiet, and comfortable.
• When you feel very tired, take short naps. Schedule naps so that you take them at about the same time every day.
• Tell your employer or teachers that you have narcolepsy. You may be able to adjust your schedule to include time for naps.
• Before bedtime:
  • Avoid bright lights and screens.
  • Relax. Try activities like reading or taking a warm bath.

Activity

• Get at least 20 minutes of exercise every day. This will help you sleep better at night and reduce daytime sleepiness.
• Avoid exercising within 3 hours of bedtime.
• If you are sleepy, do not drive or use heavy machinery.
• If possible, take a nap before driving.
• Do not swim or go out on the water without a life jacket.

Eating and drinking

• Do not drink alcohol or caffeinated beverages within 4–5 hours of bedtime.
• Do not eat a lot of food before bedtime. Eat meals at about the same times every day.

General instructions

• Take over-the-counter and prescription medicines only as told by your health care provider.
• If directed, keep a sleep diary.
• Tell your employer or teachers that you have narcolepsy. You may be able to adjust your schedule to include time for naps.
• Do not use any products that contain nicotine or tobacco, such as cigarettes and e-cigarettes. If you need help quitting, ask your health care provider.
• Keep all follow-up visits as told by your health care provider. This is important.

Contact a health care provider if:

• Your symptoms are not getting better.
• You have increasingly high blood pressure (hypertension).
• You have changes in your heart rhythm.
• You are having a hard time determining what is real and what is not (psychosis).

Get help right away if:

• You hurt yourself during a sleep attack or an attack of cataplexy.
• You have chest pain.
• You have trouble breathing.

Additonal info on Narcolepsy

Pitfalls

• Historically over diagnosed owing to a dependence on the multiple sleep latency test, which has high false-positive—and false-negative—rates for diagnosis 
  • Consider both clinical history and other tests (eg, orexin A) to reliably diagnose

Narcolepsy is a sleep disorder characterized by excessive daytime sleepiness associated with at least 1 of the following: 

Cataplexy

Orexin A (hypocretin-1) deficiency in cerebrospinal fluid

Rapid eye movement sleep latency (time from start of sleep to onset of rapid eye movement) of 15 minutes or less

Some variants of narcolepsy are associated with hypnagogic or hypnopompic hallucinations or sleep paralysis

Classification

• Type 1 narcolepsy (60%-70% of cases) 
  • Presence of cataplexy (transient loss of motor tone triggered by emotions; generally bilateral and brief, lasting less than 2 minutes) 
  • Associated with cerebrospinal fluid orexin A deficiency (less than 10% of patients with cataplexy have orexin A levels within reference range) 
• Type 2 narcolepsy (unknown prevalence)
  • Absence of cataplexy 
  • Associated with cerebrospinal fluid orexin A levels within reference range (only 10%-15% of patients have low orexin A levels) 
• Secondary narcolepsy due to medical condition (often present with cataplexy) 
  • Prader-Willi syndrome
  • Niemann-Pick disease, type C
  • Multiple sclerosis
  • Hypothalamic lesion
  • Post–head trauma
  • Postencephalitis
• Unspecified narcolepsy 

Clinical Presentation

History

• Daily excessive daytime sleepiness for at least 3 months, associated with: 
  • Frequent short naps (5-15 minutes) during daytime, usually refreshing and associated with dreams 
  • Sudden, brief sleep episodes (ie, sleep attacks) during stimulating situations (eg, driving, walking, talking)
    • Sleep attacks are generally longer in children, up to 2 to 3 hours 
  • Nocturnal insomnia 
• Presence of cataplexy 
  • Characterized by transient loss of motor tone triggered by strong emotions (eg, joy, amusement)
    • May affect all muscles (except diaphragm and extraocular muscles) or be segmental, affecting the face, speech muscles, or limbs
    • Generally bilateral; consciousness is preserved
  • Duration of seconds to minutes
  • Associated with type 1 narcolepsy
  • Occurs in 60% to 70% of patients 
• Presence of hypnagogic or hypnopompic hallucinations 
  • Vivid sensory images that occur at sleep onset (hypnagogic) or awakening (hypnopompic)
  • Hallucinations can be visual, auditory, or tactile
  • Occur in 30% to 60% of type 1 narcolepsy patients and 15% of type 2 narcolepsy patients 
• Sleep paralysis 
  • Transient inability to move or speak at sleep onset
  • Lasts seconds to minutes
  • Occurs in 50% of type 1 narcolepsy patients 
    • Sleep paralysis prevalence is unknown in type 2 narcolepsy patients

Physical examination

• Physical examination of patients with suspected narcolepsy is unremarkable and no objective findings assist in diagnosing the disorder; however, during cataplectic episodes, deep tendon reflexes are diminished or absent 

Causes

• May be caused by autoimmune destruction of orexin A neurons in the brain, particularly the lateral hypothalamus 
  • Orexin A is a neuropeptide involved in regulation of wakefulness, arousal, and appetite
  • Orexin A in cerebrospinal fluid level of 110 pg/mL or less, or less than one-third of control values, is common in patients with narcolepsy 

Risk factors and/or associations

Age

• Although onset ranges from early childhood to age 60 years, it peaks in patients aged 15 to 36 years 

Genetics

• Family history of narcolepsy
  • Increased relative risk (10- to 40-fold) of type 1 narcolepsy is found in first-degree relatives of narcolepsy patients 
  • HLA-DQB1*06:02 haplotype is associated with development of narcolepsy 
    • 98% of patients with narcolepsy with cataplexy possess this haplotype 
    • 25% of the general population possesses this haplotype 
    • 40% to 60% of patients with narcolepsy without cataplexy possess this haplotype 

Diagnostic Procedures

Primary diagnostic tools

• Diagnosis is based on the clinical manifestation of excessive daytime sleepiness, a polysomnogram followed by multiple sleep latency test, and presence or absence of cataplexy 
  • Diagnosis is confirmed with cerebrospinal fluid orexin A measurement, obtained via lumbar puncture
• HLA typing can be obtained for further supportive evidence (when present) for narcolepsy, and it is particularly useful in children owing to its relative noninvasiveness; however, HLA results are no longer included in diagnostic criteria
• Historically overdiagnosed owing to a dependence on the multiple sleep latency test, which has high false-positive (and false-negative) rates for diagnosis 
  • Consider both clinical history and other tests (eg, orexin A test) to reliably diagnose

Laboratory

• Orexin A level of 110 pg/mL or less, or below one-third of control values—obtained via lumbar puncture—is indicative of type 1 narcolepsy 
• Obtain HLA typing, particularly in children
  • Positive finding of HLA-DQB1*06:02 haplotype is supportive of a narcolepsy diagnosis, but it is not diagnostic because it lacks specificity 

Functional testing

• Polysomnography and multiple sleep latency test 
  • Indicated for all adult patients and children aged 6 years and older with signs and symptoms suggestive of narcolepsy according to clinical presentation 
    • Discontinue any sedating or stimulatory medications 2 weeks before the test to avoid inaccurate results (ie, washout) 
    • Demonstrate a regular sleep-wake cycle by maintaining a sleep diary or by using actigraphy (measurement of activity and rest by a small, worn sensor) during that time 
    • At least 6 hours of nocturnal sleep are necessary before performing the test 
  • Overnight polysomnogram (of at least 6 hours) helps to exclude other causes of night sleep disruption (eg, sleep apnea, periodic limb movement disorder) 
  • Next day multiple sleep latency test can measure the ability to sleep reflected by sleep latency during 20-minute nap opportunities (5 nap opportunities at 2-hour intervals), including the following 2 parameters: 
    • Mean sleep latency: arithmetic mean of all naps or nap opportunities
    • Number of sleep-onset rapid eye movement periods: rapid eye movement sleep periods within 15 minutes of sleep onset, occurring for greater than 15 seconds in a 30-second period 
  • Continuous 24-hour polysomnogram is performed in toddlers and children younger than 6 years 
  • Results
    • Sleep latency of 8 minutes or less and 2 or more sleep-onset rapid eye movement periods are diagnostic of narcolepsy 
      • Diagnostic specificity of multiple sleep latency test is 60%; when 2 or more sleep-onset rapid eye movement periods are present, diagnostic specificity increases to 95%
    • High false-positive and false-negative rates for diagnosis 
      • Among patients without narcolepsy, 6% of males and 1.5% of females have test results that are diagnostic for this condition 
      • 6% of patients with sleep-disordered breathing and 4% of patients with other sleep disorders test positive on the multiple sleep latency test 
      • Some patients with orexin A deficiency and diagnosis of narcolepsy with cataplexy have normal multiple sleep latency test results 
      • Underlies the importance of interpreting multiple sleep latency test results within the clinical context

Procedures

Lumbar puncture 

General explanation

• Insertion of a hollow-bore needle between the vertebral bodies into the subarachnoid space to obtain a specimen of cerebrospinal fluid
• Cerebrospinal fluid orexin A level is measured using a radioimmunoassay

Indication

• To collect and examine cerebrospinal fluid for diagnostic clarity when the multiple sleep latency test is not available or feasible (recommended, but not required)

Contraindications

• Uncontrolled coagulopathy
• Skin infection at site of needle insertion
• Patient at risk of brain herniation 
  • Best predictors of precipitating herniation (even with normal CT result) include:
    • Deteriorating level of consciousness (particularly to a Glasgow Coma Scale score of 11 or less)
    • Brainstem signs (eg, pupillary changes, abnormal posturing, irregular respirations)
    • Very recent seizure

Complications

• Post–dural puncture headache
• Back pain
• Radicular injury
• Infection
  • Epidural abscess
  • Meningitis
  • Diskitis
  • Vertebral osteomyelitis
• Epidural hematoma
• Cerebral herniation
• Epidermoid tumor formation

Interpretation of results

• Orexin A level of 110 pg/mL or less, or below one-third of control values, is indicative of type 1 narcolepsy 

Differential Diagnosis

Most common

• Disorders with excessive daytime sleepiness
• Disorders with cataplexy

Treatment Goals

• Minimize or eliminate excessive daytime sleepiness 
• Minimize or eliminate cataplectic episodes 

Disposition

Recommendations for specialist referral

• Refer to pediatric neurologist when narcolepsy is suspected in children, especially those younger than 6 years, owing to the difficulty in making the diagnosis
• Neurologic consultation is recommended when the diagnosis is unclear and assistance is needed for medication management

Treatment Options

First step in treating narcolepsy is to provide guidance about appropriate sleep hygiene 

Some patients may prefer to manage without medication and may be able to adjust nap schedules that allow reasonable control 

• Limit naps to approximately 15 minutes
• In prepubertal and pubertal children, at least 2 naps (lunchtime and between 4:00 and 5:00 PM) are recommended 

Most patients are managed with drug therapy 

• Central nervous system stimulants
  • Those frequently used include: 
    • Modafinil
      • First line treatment for patients with excessive daytime sleepiness of mild to moderate degree
      • May also be used in combination with amphetamines if needed to control daytime sleepiness 
    • Armodafinil
      • Indicated to improve wakefulness in adult patients with excessive daytime sleepiness
    • Solriamfetol
      • Indicated to improve wakefulness in adult patients with excessive daytime sleepiness
    • Methylphenidate 
      • Indicated in patients with daytime sleepiness when modafinil or armodafinil is insufficient
    • Amphetamines 
      • Indicated in patients with daytime sleepiness when other medications are ineffective
  • Tolerance can develop with use of stimulant medications; switching between drugs or scheduling drug holidays can be effective in avoiding tolerance 
  • Methylphenidate or modafinil appear to be relatively safe for use in children aged 6 to 15 years 
• γ-aminobutyric acid receptor agonist
  • Sodium oxybate 
    • First line treatment for adult patients with cataplexy and useful in patients with moderate to severe daytime sleepiness
    • Highly effective, although stimulants may still be required to treat daytime sleepiness 
    • Only available through a restricted distribution program (eg, Xyrem Risk Evaluation and Mitigation Strategy program) owing to the need to monitor for abuse or misuse and respiratory depression that may be increased by interacting substances (eg, sedatives)
• Antidepressants 
  • Effective to decrease the incidence of cataplexy; also used to suppress hypnagogic hallucinations and sleep paralysis if severe
    • Venlafaxine
    • Fluoxetine
    • Clomipramine

Drug therapy

• Stimulant medication is prescribed as first line drug therapy to decrease daytime sleepiness and improve symptoms in a large majority of patients 
• Treatment of excessive daytime sleepiness 
  • Wake-promoting agent
    • Modafinil 
      • Typically provided as first line alternative to central nervous system stimulants
      • Modafinil Oral tablet; Adults, including Geriatric Adults: 200 mg PO once daily as a single dose in the morning. While doses up to 400 mg PO once daily have been well tolerated, there is no consistent evidence that doses greater than 200 mg/day confer additional clinical benefit. Max: 400 mg/day PO.
    • Armodafinil
      • Armodafinil Oral tablet; Adults, including Geriatric Adults: 150 mg to 250 mg PO once daily as a single dose in the morning. In geriatric adults, use lowest effective dose due to the possibility of adverse effects from decreased drug elimination.
    • Solriamfetol 
      • Dopamine and norepinephrine reuptake inhibitor
      • Solriamfetol Oral tablet; Adults: Initially, 75 mg PO once daily upon awakening. If needed, increase the dose to 150 mg PO once daily after at least 3 days. Max: 150 mg once daily. Avoid administering within 9 hours of planned bedtime due to possible sleep interference. Periodically re-assess the need for treatment.
  • Central nervous system stimulants 
    • Methylphenidate
      • Given in daily divided doses
        • Therapy is initiated with immediate-release formulation until an effective daily dose is determined, then total daily dose is converted to a sustained-release formulation
      • Use caution when prescribing to patients with history of drug dependence or cardiac diseases 
      • Methylphenidate Hydrochloride Oral tablet; Children and Adolescents 6 years and older: 5 mg PO twice daily before breakfast and lunch. Increase by 5 to 10 mg/day at weekly intervals. Max: 60 mg/day.
      • Methylphenidate Hydrochloride Oral tablet; Adults: Average dose 20 to 30 mg/day; range 10 to 60 mg/day PO in 2 to 3 divided doses, 30 to 45 minutes before meals.
    • Amphetamines
      • Dextroamphetamine
        • Dextroamphetamine Sulfate Oral tablet; Children 6 to 11 years: 5 mg PO once daily in the morning. May titrate daily dose by 5 mg increments at weekly intervals. Max: 60 mg/day. Use minimum effective dose.
        • Dextroamphetamine Sulfate Oral tablet; Adults, Adolescents, and Children 12 years and older: Initially, 10 mg PO once daily in the morning. May titrate by 10 mg increments at weekly intervals to the minimum effective dose. Daily dose may be given in 1 to 3 divided doses at 4 to 6 hour intervals. Avoid late evening doses. Reduce dose if anorexia or insomnia occur. Usual dosage range: 5 to 60 mg/day PO, given in divided doses. Max: 60 mg/day PO.
      • Amphetamine-dextroamphetamine
        • Amphetamine Aspartate, Amphetamine Sulfate, Dextroamphetamine Saccharate, Dextroamphetamine Sulfate Oral tablet; Children 6 to 11 years: 5 mg PO once daily in the morning. Titrate by 5 mg increments at weekly intervals to minimum effective dose. Daily dose may be given in 1 to 3 divided doses at 4 to 6 hour intervals. Max: 60 mg/day.
        • Amphetamine Aspartate, Amphetamine Sulfate, Dextroamphetamine Saccharate, Dextroamphetamine Sulfate Oral tablet; Adults, Adolescents, and Children 12 years and older: Initially, 10 mg PO once daily. Titrate by no more than 10 mg/day at weekly intervals to the minimum effective dose. Max: 60 mg/day PO.
• Treatment of excessive daytime sleepiness and cataplexy
  • γ-aminobutyric acid receptor agonist
    • Sodium oxybate 
      • Only FDA-approved drug for cataplexy 
      • Central nervous system depressant
      • Administer orally daily, increasing dose every 4 weeks; may take 8 to 12 weeks to have optimal effect 
      • Prescribing requires enrollment in the Xyrem Risk Evaluation and Mitigation Strategy program; information is available from a pharmacist
      • Patients treated with sodium oxybate should not actively experience obstructive sleep apnea or should be fully adherent to nasal CPAP device therapy
      • Sodium Oxybate (Gamma Hydroxybutyrate Or Ghb) Oral solution; Children and Adolescents 7 to 17 years weighing less than 20 kg: Specific dosing recommendations are not available; consider a lower starting dosage, lower weekly dosage increases, and lower total maximum dosage. For patients weighing 20 to 29 kg, the initial dosage is 2 grams or less/night PO, divided into 2 equal doses, the first given at bedtime and the second given 2.5 to 4 hours later. May increase dosage by no more than 1 gram/night (0.5 gram/dose) at weekly intervals. Max: 6 grams/night. For patients who sleep more than 8 hours/night, the first dose can be given at bedtime or after an initial period of sleep. Unequal dosages may be required for some patients to achieve optimal treatment.
      • Sodium Oxybate (Gamma Hydroxybutyrate Or Ghb) Oral solution; Children and Adolescents 7 to 17 years weighing 20 to 29 kg: 2 grams or less/night PO initially, divided into 2 equal doses, the first given at bedtime and the second given 2.5 to 4 hours later. May increase dosage by no more than 1 gram/night (0.5 gram/dose) at weekly intervals. Max: 6 grams/night. For patients who sleep more than 8 hours/night, the first dose can be given at bedtime or after an initial period of sleep. Unequal dosages may be required for some patients to achieve optimal treatment.
      • Sodium Oxybate (Gamma Hydroxybutyrate Or Ghb) Oral solution; Children and Adolescents 7 to 17 years weighing 30 to 44 kg: 3 grams or less/night PO initially, divided into 2 equal doses, the first given at bedtime and the second given 2.5 to 4 hours later. May increase dosage by no more than 1 gram/night (0.5 gram/dose) at weekly intervals. Max: 7.5 grams/night. For patients who sleep more than 8 hours/night, the first dose can be given at bedtime or after an initial period of sleep. Unequal dosages may be required for some patients to achieve optimal treatment.
      • Sodium Oxybate (Gamma Hydroxybutyrate Or Ghb) Oral solution; Children and Adolescents 7 to 17 years weighing 45 kg or more: 4.5 grams or less/night PO initially, divided into 2 equal doses, the first given at bedtime and the second given 2.5 to 4 hours later. May increase dosage by no more than 1.5 grams/night (0.75 grams/dose) at weekly intervals. Max: 9 grams/night. For patients who sleep more than 8 hours/night, the first dose can be given at bedtime or after an initial period of sleep. Unequal dosages may be required for some patients to achieve optimal treatment.
      • Sodium Oxybate (Gamma Hydroxybutyrate Or Ghb) Oral solution; Adults: 4.5 grams/night PO initially, divided into 2 equal doses of 2.25 grams, the first given at bedtime and the second given 2.5 to 4 hours later. May increase dosage by 1.5 grams/night (0.75 grams/dose) at weekly intervals. Effective dosage range: 6 to 9 grams/night. Doses more than 9 grams/night have not been studied and should not ordinarily be administered.
• Treatment of cataplexy, severe hypnagogic hallucinations, or severe sleep paralysis 
  • Venlafaxine 
    • Off-label indication
    • Venlafaxine Hydrochloride Oral tablet, extended-release; Adults: Initially, 75 mg PO once daily. If needed, may increase further by 75 mg/day at intervals of no less than every 4 days. Max: 225 mg/day.
  • Fluoxetine 
    • Off-label indication
    • Fluoxetine Hydrochloride Oral capsule; Adults: 20 mg/day PO initially. May increase the dose every month by 10 to 20 mg if needed. Max: 80 mg/day. May divide into 2 doses if dosage is 20 mg/day or more, given at morning and at noon.
  • Clomipramine 
    • Off-label indication
    • Clomipramine Hydrochloride Oral capsule; Adults: Initially, 25 mg PO once daily, may gradually increase in the first 2 weeks to 100 mg/day PO, given in divided doses. Max: 250 mg/day. After titration, the total daily dose may be given at bedtime to minimize daytime sedation.

Nondrug and supportive care

• Counsel patients to improve sleep hygiene 
  • Maintain regular sleep schedule to get adequate sleep (most patients require 7-9 hours)
  • Schedule regular naps throughout the day to improve alertness 
  • Allow 1-hour period before bedtime for relaxation 
• Avoid stimuli (eg, alcohol, heavy meals) that promote sleep attacks 
• Avoid stimulants (eg, caffeine, nicotine) 6 hours before bedtime 
• Engage in regular exercise to promote wakefulness (but not close to bedtime) 

Special populations

• Pregnant and/or breastfeeding women
  • Consider potential risks of medical therapy for narcolepsy along with potential benefits. No teratogenicity has been shown, but none of the drugs typically used for narcolepsy have been specifically studied 
    • If a patient being treated becomes pregnant, can reassure her about the absence of teratogenic effects associated with central nervous system stimulants, antidepressants, or sodium oxybate. May withdraw medications during pregnancy as further caution
      • For those maintained on medical therapy during pregnancy, consideration is given to temporarily discontinue some or all of the drugs used near delivery due to their possible effects on the newborn (eg, sedation, withdrawal)
    • For women who want to become pregnant, either stop medication before pregnancy occurs or monitor closely for pregnancy and stop medical therapy with first positive pregnancy test
    • Because all the medications employed in narcolepsy pass into breast milk, patient should feed baby formula if she wants to continue or resume medical therapy after delivery

Monitoring

• Regular monitoring is required to determine the effectiveness of therapy and identify any adverse effects
  • Monitor sleepiness and subjective response to medication using an objective measure, such as the Epworth Sleepiness Scale 
  • Once stabilized on a stimulant or other medication, patients are seen at least once a year, preferably every 6 months; monitor for sleep disturbances, cardiovascular or metabolic abnormalities, and mood changes 
• Because there is a risk of respiratory depression for those being treated with sodium oxybate, patients prescribed this medication must be monitored for obstructive sleep apnea or must adhere to nasal CPAP device therapy 
  • If obstructive sleep apnea is not present initially, monitor with nocturnal oximetry for its development:
    • Every 2 years for all patients treated with sodium oxybate
    • Annually for obese patients (with BMI greater than 30)
    • After a 6.8-kg weight gain
    • After an increase in snoring (as indicated by the visual analog snoring severity scale)
    • After initiating a new sedating medication (which may worsen obstructive sleep apnea)

Complications

• Increased incidence of accidents owing to daytime sleepiness
• Difficulty with professional and interpersonal relationships owing to daytime sleepiness

Prognosis

• There is no cure for narcolepsy; however, symptoms can improve approximately 80% with drug therapy and good sleep hygiene 
  • Patient must make adjustments to manage wakefulness and sleepiness and maintain regularity in sleep/wake patterns 
  • Follow medication closely

Sources

Leschziner G: Narcolepsy: a clinical review. Pract Neurol. 14(5):323-31, 2014 Reference