Clinic Locations

Woolcock Sleep Clinic
Phone: (02) 9114 0000
Address: 431 Glebe Point Road, Glebe, NSW, 2037 Email: [email protected]
Royal Prince Alfred Hospital
Phone: (02) 9515 6655
Address: Level 11, Main Block, Missenden Road, Camperdown, NSW, 2050
Integrated Sleep Health
Phone: (02) 9331 7546
Address: Suite 1, Level 7, 26 College Street, Darlinghurst, NSW, 2010 Email: [email protected]

Professor Ron Grunstein AM

Professor of Sleep Medicine


Idiopathic Hypersomnolence / Hypersomnia

Like narcolepsy, idiopathic hypersomnolence is a condition characterised by excessive sleepiness. Patients also experience difficulty in waking (either in the morning or at the end of nap periods during the day). The term idiopathic means ‘of unknown cause’.

As with narcolepsy, patients with this condition often sleep for long periods but, unlike patients with narcolepsy, in whom sleep attacks can occur anytime without warning, patience with idiopathic hypersomnolence have a better control over their sleep, and do not suffer from cataplexy or the other features of the full narcolepsy syndrome, such as sleep paralysis, hallucinations and automatisms.

Although about 25% of patients experience spontaneous improvement in their condition, it can be life-long and can require treatment with similar stimulant medications to those which are used for treating narcolepsy. Patients require accurate testing for hypersomnia and specific tests are required for approval of some medications. Our current research focuses on clinical care of patients with idiopathic hypersomnia and the role of new medications.

Suffers of Idiopathic ("cause unknown") Hypersomnolence ("excessive sleepiness") have 'sleep attacks' at irregular and unscheduled times.

Suffers of Idiopathic (“cause unknown”) Hypersomnolence (“excessive sleepiness”) have ‘sleep attacks’ during irregular times.