Excessive daytime sleepiness (hypersomnia)

Excessive daytime sleepiness (hypersomnia) is a condition where people fall asleep repeatedly during the day.

Check if it's hypersomnia

Excessive daytime sleepiness (hypersomnia) is different from feeling tired all the time.

If you have hypersomnia, you may:

Non-urgent advice: See a GP if:

  • you often fall asleep during the day
  • sleepiness is affecting your life

What happens at your appointment

To find out why you're sleeping excessively, a GP might:

Treatment for excessive sleepiness will depend on what's causing it. It may include medicine to help keep you awake.

Causes of hypersomnia

Sometimes other conditions may be related to excessive sleepiness (hypersomnia). These conditions can have additional symptoms.

Symptoms and possible causes
Additional symptoms Possible cause

Feeling the need to sleep anywhere, sometimes without warning


Loud snorting, breathing and snoring at night

Sleep apnoea

An unusual feeling in your legs, particularly at night

Restless legs syndrome

Low mood, little interest in things


Mood swings that range from extreme highs (mania) to extreme lows

Bipolar disorder

Problems recovering after physical activity, problems with thinking, memory or concentration

Myalgic encephalomyelitis or chronic fatigue syndrome (ME/CFS)

Some medicines, drinking too much alcohol and taking drugs can also cause excessive daytime sleepiness.

Idiopathic hypersomnia

Idiopathic hypersomnia is when someone sleeps for long periods and wakes up feeling confused or irritable (known as sleep inertia) and not refreshed.

There's no known cause for idiopathic hypersomnia.

Things you can try to help your sleeping habits

Changing your sleep habits may not cure excessive daytime sleepiness (hypersomnia), but it might help you feel better.

Try to:

It might also help to talk to your family and friends about your excessive daytime sleepiness so they're aware of it.


If you're diagnosed with hypersomnia you'll need to tell the Driver and Vehicle Licensing Agency (DVLA) and you may not be able to drive.

Find out about the rules on excessive sleepiness and driving from GOV.UK

Page last reviewed: 23 June 2023
Next review due: 23 June 2026