Diagnosing and treating Narcolepsy

Sleepiness can be a symptom of many sleep disorders. Which is why it’s important to get a sleep study to diagnose and treat what may be causing your sleepiness.

What is Narcolepsy?

Narcolepsy is a spectrum of chronic sleep disorders in which persons have overwhelming daytime drowsiness and attacks of sleep, in the absence of any other Sleep Disorder. Those with Narcolepsy often have trouble staying awake for long periods of time.

The classic tetrad of narcolepsy includes:

• Excessive Daytime Sleepiness,
• Cataplexy (sudden loss of muscle tone),
• Sleep Paralysis, and
• Hypnagogic Hallucinations.

Often those with Narcolepsy patients also suffer from sleep disruption.

How is Narcolepsy diagnosed?

A Multiple Sleep Latency Test (MSLT) is required to diagnose Narcolepsy. This includes an overnight sleep study, timed nap opportunities the following day, as well as a urinalysis.

A home (or ambulatory) sleep study won’t provide the necessary information to diagnose Narcolepsy. A home sleep study will also not allow you PBS access to medications used for the treatment of Narcolepsy.

At overseas centres, CSF hypocretin/orexin levels can be used (noting that these can be normal in some variants of Narcolepsy). This test is not widely available in Australia.

What treatment is available for Narcolepsy?

There are several treatments available for Narcolepsy. These include :

Behavioural therapy

To manage Narcolepsy symptoms in the long term, good sleep hygiene is crucial. Having enough sleep at night is extremely, and timed daytime naps can be useful too. Avoiding shift work and generally any disruption to the Circadian Rhythm is at the centre of all treatments.

Medications

There are many medications available to help treat Narcolepsy, but each has their own pros and cons.

• CNS stimulants
  • Methylphenidate (Ritalin, Concerta) or Dexamphetamine work well, but have long-term implications.
  • Modafinil and Armodafinil (Modavigil and Nuvigil) are generally better tolerated than amphetamine-based medications, but still require long-term maintenance.
• CNS depressants
  • The only proven CNS depressant use in Narcolepsy is Sodium Oxybate (Xyrem), for which prescribing is overseen by state and federal bodies. Careful consideration is made to select those who should be on Xyrem and the potential side effects.

Other medications available overseas include Pitolisant and Solriamfetol. We’re hopeful they may eventually become available in Australia.

Our Sleep Specialists have experience in the diagnosis, counselling and treatment of Narcolepsy and Narcolepay variants such as Idiopathic Hypersomnia. If you’d like to know more, contact us now.

Contributed by Dr Dien Dang