Introduction

'Hypersomnia' means excessive sleep or sleepiness that interferes with everyday life.

It can have many possible causes, including conditions such as Narcolepsy , sleep apnoea or restless legs syndrome ;severe sleep deprivation; depression ; certain medications (such as tranquillisers); or drug and alcohol misuse .

However, some people with hypersomnia will not have an underlying medical condition and there will be no obvious explanation for it they have it throughout the day, despite sleeping for a very long time at night. This is known as "idiopathic" or primary hypersomnia.

The rest of this page focuses on idiopathic hypersomnia.

Content supplied by the NHS Website

Medically Reviewed by a doctor on 4 Jan 2017