What Are the Signs of Narcolepsy?

Excessive daytime sleepiness and inability to stay awake are hallmarks of the sleep disorder called narcolepsy.

Narcolepsy is a chronic neurological disorder that causes symptoms such as excessive daytime sleepiness (EDS), sudden muscle weakness (cataplexy), the transition from being awake to being asleep (hypnagogic hallucinations), and sleep paralysis. People with narcolepsy may fall asleep suddenly (sleep attack), which can make it hard to carry out normal daily activities.

The four main symptoms of narcolepsy in adults are:

• Excessive daytime sleepiness (EDS)
  • EDS is the main symptom of narcolepsy
  • EDS must be present for at least 3 months to diagnose narcolepsy
  • Severe EDS leads to involuntary sleepiness during daily activities such as driving, eating, or talking
  • Sleepiness may be severe and constant, with periods of falling asleep without warning (sleep attacks)
• Sudden muscle weakness (cataplexy)
  • Cataplexy is typically triggered by emotions such as laughter and anger
  • Severe cataplexy may cause a person to fall
  • Subtle forms of cataplexy may occur with partial loss of muscle tone such as a head nod, altered speech, and knee buckling
  • Breathing and eye movements are maintained
• Transitioning from being awake to being asleep (hypnagogic hallucinations)
• Sleep paralysis
  • Being unable to move in the moments before falling asleep or awakening  
  • Hallucinations frequently occur along with the paralysis
  • Breathing and eye movements are maintained
  • Paralysis occurs less often if the patient is sleeping in an uncomfortable position
  • Paralysis may be relieved by stimulating the senses, such as touching or speaking to the person

Other symptoms of narcolepsy include:

• Frequent short naps during the day
• Difficulty sleeping at night 
• Night-time compulsive behaviors such as sleep-related eating disorder and nocturnal smoking 
• Obesity

Children with narcolepsy rarely have all four main symptoms. Symptoms of narcolepsy in children may include: 

• Restlessness and overactivity 
• Falling grades in school
• Inattentiveness
• Mood swings
• Involuntary movements that may range from negative such as low muscle tone, to active, such as involuntary muscle movements
• Cataplectic facies, which is characterized by repetitive mouth opening, sticking the tongue out, and drooping eyelids

The cause of narcolepsy is unknown. It is thought genetics may play a role in developing the condition. 

Narcolepsy seems to occur when a person has low levels of a certain brain chemical called hypocretin, which helps control wakefulness and REM sleep. The deficiency in hypocretin may be the result of an autoimmune response, in which the body’s immune system mistakenly attacks the parts of the brain that produce hypocretin.

Certain triggers may also increase a person's risk of developing narcolepsy including:

• Hormonal changes, such as during puberty or menopause
• Significant psychological stressors
• Sudden changes in sleep patterns
• Infection, such as swine flu or a streptococcal infection
• Autoimmune disorders

Narcolepsy may also be the result of an underlying condition that damages the areas of the brain that produce hypocretin. Secondary narcolepsy may develop after:

• Head injury
• Brain tumor
• Multiple sclerosis (MS)
• Encephalitis

Risk factors for developing narcolepsy include:

• Age – symptoms of the condition usually start between the ages of 15 and 25, but it can occur at any age. 
• Family history of narcolepsy increases a person’s risk of getting it by 20 to 40 times 

If narcolepsy is suspected, patients are sent for evaluation in a sleep study. In a sleep study, patients are admitted to a sleep lab where bodily functions are monitored overnight. Then another test is performed during the day where patients are asked to nap. 

People who have narcolepsy will have abnormal sleep patterns both during the night and during the daytime naps. 

Narcolepsy may be treated with behavior changes, such as:

• Maintaining a regular sleep schedule
• Getting 7.5 to 8 hours of sleep nightly
• Scheduling naps in the day, especially before important events
• Exercising regularly
• Relaxing before bedtime
• Avoiding large meals before bed
• Avoiding smoking and drinking alcohol
• Avoiding use of caffeine within a few hours of regularly scheduled bedtime
• Avoiding medicines that can make you drowsy, such as some allergy medicines

If behavior changes don’t work, narcolepsy may also be treated with medications, including:

• Stimulants
  • Methylphenidate (Ritalin)
  • Modafinil (Provigil)
  • Armodafinil (Nuvigil)
  • Amphetamines
  • Solriamfetol
• Codeine (in patients for whom stimulant treatment is problematic) 
• Medications to treat cataplexy
  • Sodium oxybate (Xyrem) (also treats excessive daytime sleepiness/EDS)
  • Antidepressants such as clomipramine (Anafranil) and fluoxetine (Prozac); off-label use)
  • Dopamine/norepinephrine reuptake inhibitors such as solriamfetol (Sunosi)
• Histamine H3 antagonists/inverse agonists 
  • Pitolisant (Wakix) 

Narcolepsy is a life-long condition that can generally be managed. Most patients with narcolepsy live a normal life span. 

If left untreated, complications of narcolepsy include:

• Social isolation due to embarrassment from symptoms
• Interpersonal stress in relationships
• Sexual dysfunction
• Difficulty working due to:
  • Sleep attacks
  • Memory problems
  • Cataplexy
  • Interpersonal problems
  • Personality changes
  • Perception by coworkers that the patient is lazy, inattentive, and lacking motivation
• May be falsely suspected of drug abuse
• Poor school performance, social impairment, ridicule from peers, and dysfunction in other activities of normal childhood development in children