Narcolepsy

Narcolepsy is a chronic neurological sleep-wake disorder characterised by persistent excessive daytime sleepiness. This can involve difficulty remaining awake, an irresistible need to sleep and unintended episodes of sleep during the day. There are two types of narcolepsy: narcolepsy type 1 (NT1) and narcolepsy type 2 (NT2). Although excessive daytime sleepiness is central to both, they do not have the same cause or clinical features.

Narcolepsy type 1

Narcolepsy type 1 (NT1), sometimes called narcolepsy with cataplexy, is caused by the loss of specific nerve cells in the brain’s hypothalamus that produce orexin (hypocretin). Orexin is a chemical messenger essential for regulating wakefulness and rapid eye movement (REM) sleep.

This loss is believed to result from an autoimmune response in which the immune system mistakenly attacks the body’s own orexin-producing cells.

Genuine cataplexy is the characteristic feature that distinguishes NT1 from other central disorders of hypersomnolence. Cataplexy may not be obvious at first and can begin after other narcolepsy symptoms have developed. A low cerebrospinal fluid orexin level can confirm NT1 before cataplexy is recognised or develops. [1,2]

Download the Narcolepsy Type 1 factsheet

Narcolepsy type 2

Narcolepsy type 2 (NT2), sometimes called narcolepsy without cataplexy, is characterised by persistent excessive daytime sleepiness. People with NT2 generally have normal orexin levels, and its cause is unknown.

NT2 is less well understood than NT1. Researchers believe that NT2 may represent more than one underlying condition. The clinical pattern varies, and there is overlap between NT2 and Idiopathic Hypersomnia. Current testing cannot reliably separate them. [4–6]

Download the Narcolepsy Type 2 factsheet

Symptoms of narcolepsy

Excessive daytime sleepiness

Excessive daytime sleepiness is central to both NT1 and NT2. It may cause:

difficulty remaining awake
an irresistible need to sleep
unintended episodes of sleep
sleep attacks

Short naps are often refreshing for people with NT1, although the sleepiness returns. Naps may also be short and refreshing for some people diagnosed with NT2, but not for others. [1,4]

Other sleep symptoms

Other symptoms associated with narcolepsy vary but may include:

Sleep paralysis: A temporary inability to move or speak when falling asleep or waking up. Episodes usually last from a few seconds to a few minutes.
Sleep-related hallucinations: Hypnagogic hallucinations occur while falling asleep, and hypnopompic hallucinations occur while waking up. These vivid sensory experiences may involve seeing, hearing or feeling something that is not present.
Disturbed or fragmented nighttime sleep: Repeated awakenings, vivid dreams and difficulty maintaining sleep are common in NT1.
Different sleep and nap patterns in NT2: People with NT2 do not share one consistent sleep pattern. Prolonged nighttime sleep, sleep inertia, unrefreshing naps and disrupted nighttime sleep are also reported.

Sleep paralysis and sleep-related hallucinations are more closely associated with NT1. Many diagnosed with NT2 do not experience either symptom. [1,3,4]

Understanding genuine cataplexy

Cataplexy is a sudden, involuntary loss of muscle tone or muscle control that occurs while a person is awake. It is triggered by strong emotion, most characteristically laughter, amusement, excitement, joking, and occasionally anger.

Cataplexy can cause partial muscle weakness, such as the jaw sagging, the head dropping or the knees buckling. Complete paralysis affecting the whole body is rare. The person always remains conscious. [1,2]

Cataplexy is not fainting or a sleep attack.

Other conditions can also cause temporary weakness, falls or collapse. Identifying genuine cataplexy requires careful consideration of what triggers the episode, what happens during it, how long it lasts, whether consciousness is preserved, which parts of the body are affected and what happens immediately afterwards.

If you pass out, black out, lose consciousness or have unexplained episodes of weakness, falls or collapse, speak to your doctor so the cause can be investigated.

Download Identifying Genuine Cataplexy in Narcolepsy

Narcolepsy in children and adolescents

Narcolepsy often begins during childhood or adolescence, although it can develop at any age.

In children and adolescents, sleepiness may appear as irritability, hyperactivity, inattention, behavioural change or declining school performance.

NT1 can look different near the onset of childhood narcolepsy. Cataplexy may include facial slackening, drooping eyelids, repeated mouth opening, tongue protrusion, an unsteady gait or additional movements alongside loss of muscle tone. Rapid weight gain can also occur around disease onset.

Insufficient sleep and delayed sleep timing are common among young people and can affect sleep study results. Assessment by a clinician familiar with paediatric narcolepsy and other central disorders of hypersomnolence is important. [10,11]

Diagnosis

Diagnosis begins with a detailed clinical history, including the pattern and onset of sleepiness, a careful description of possible cataplexy, nighttime sleep, sleep schedule, medications and other factors that may contribute to sleepiness. Information from someone who has witnessed cataplexy can be helpful.

An overnight sleep study, called polysomnography, is followed the next day by a Multiple Sleep Latency Test (MSLT). The MSLT measures how quickly a person falls asleep and whether REM sleep occurs soon after sleep onset. Results must be interpreted in the context of adequate prior sleep, medication effects and the full clinical picture. [1]

Diagnosing NT1

NT1 may be identified through a characteristic history of genuine cataplexy together with sleep study findings. Measurement of orexin in cerebrospinal fluid can confirm NT1. This is particularly valuable when cataplexy is absent, has not yet developed or reported episodes are not clearly genuine cataplexy. [1]

Diagnosing NT2

Before NT2 is diagnosed, other possible causes of sleepiness must be considered and ruled out. These include insufficient sleep, circadian rhythm sleep-wake disorders, sleep apnea, medication or substance effects and other medical, neurological or mental health conditions.

Under current diagnostic criteria, NT2 depends heavily on the MSLT. This is an important limitation because MSLT results are much less stable in NT2 than NT1. On repeat testing, people diagnosed with NT2 often no longer meet the same MSLT criteria. They may instead meet the criteria for Idiopathic Hypersomnia or no longer meet the MSLT criteria for either disorder. [4,5,7–9]

Treatment and management

There is currently no cure for narcolepsy. Treatment is individualised according to the type of narcolepsy, the symptoms experienced and the person’s circumstances.

Treatment may include:

Daytime sleepiness: Wake-promoting and stimulant medicines used in Australia include dexamphetamine, modafinil and armodafinil.
Sodium oxybate: Can improve excessive daytime sleepiness, cataplexy and disrupted nighttime sleep. It was registered in Australia in July 2026 for narcolepsy in adults and in children and adolescents aged seven years and older. Access and subsidy arrangements should be discussed with the treating specialist.
Cataplexy: Some antidepressant medicines are prescribed to reduce cataplexy.
Daily management: Planned brief naps and a regular sleep-wake schedule may help manage symptoms. Improvement in general health and wellbeing through healthy sleep practices, nutrition and fitness can help improve overall quality of life for people with narcolepsy.

Any other sleep disorders should also be appropriately treated. [12,13]

Important information about modafinil and armodafinil

These medicines can reduce the effectiveness of hormonal contraception. The Therapeutic Goods Administration also advises against using modafinil and armodafinil during pregnancy because these medicines are suspected to cause birth defects and miscarriage.

Discuss contraception, pregnancy planning and medication safety with the prescribing doctor or pharmacist. [14]

Living with narcolepsy

Narcolepsy can affect education, employment, driving, relationships, independence and overall quality of life. Medication may improve symptoms, but it may not restore normal alertness or address every impact of the condition.

Appropriate adjustments at school, university or work may be needed. Reliable information and connection with other people who understand can also make an important difference.

Living with Narcolepsy community group

Hypersomnolence Australia’s Living with Narcolepsy community group brings people diagnosed with narcolepsy together to share conversation, connection and lived experience. The group meets online each month and is guided by an experienced facilitator.

Learn more and register