Tiredness and fatigue


Tiredness and fatigue
Tiredness and fatigue

It's normal to feel tired sometimes. But if you're tired all the time and do not know why, it could be a sign of a problem.

Causes of tiredness and fatigue

Common causes of tiredness and fatigue include:

  • not getting enough sleep or finding it hard to get to sleep (insomnia)
  • an unhealthy lifestyle (such as having an unhealthy diet and not getting much exercise)
  • stressdepression and dealing with life challenges, such as bereavement or looking after a new baby
  • hormonal changes (such as during puberty, pregnancy or the menopause)
  • some illnesses, like glandular fever and COVID-19
  • some medical treatments and medicines, like chemotherapy, which can cause drowsiness for a while

But if you cannot explain why you're tired and it's been going on for a while and not getting any better, it may be a sign of a medical condition.

Your symptoms might give you an idea of what's causing your tiredness or fatigue. But do not self-diagnose – see a GP if you're worried.

Conditions that can cause tiredness and fatigue

Symptoms: Tired during the day because of waking up at night, making gasping, snorting or choking noises at night and loud snoring. Possible cause: Sleep apnoea

Symptoms: Lack of energy, noticeable heartbeats (heart palpitations), shortness of breath and pale skin. Possible cause: Iron deficiency anaemia

Symptoms: Very tired, feeling very thirsty, peeing more often than usual (particularly at night), weight loss. Possible cause: Diabetes

Symptoms: Tired all the time, finding it hard to stay still, feeling nervous, anxious and irritable, muscle weakness. Possible cause: Overactive thyroid (hyperthyroidism)

Symptoms: Extreme fatigue for at least 3 months (making it very hard to do daily activities), problems with thinking, memory and concentration, flu-like symptoms. Possible cause: Myalgic encephalomyelitis or chronic fatigue syndrome (ME/CFS)

Things you can do to help with tiredness or fatigue

There may be things you can do to help with your tiredness or fatigue.


  • have a healthy diet and exercise regularly
  • try to stick to the same sleep times and aim for 6 to 9 hours of sleep
  • try to relax a couple of hours before your sleep time (read, or listen to music or a podcast)
  • have a relaxing sleeping area (not too bright, noisy or warm)


  • do not smoke
  • do not drink too much alcohol
  • do not eat, have caffeine or exercise in the couple of hours before sleep
  • do not use smartphones or screens in the hour before sleep

More information

Better Health: how to fall asleep faster and sleep better
Better Health: dealing with life's challenges

See a GP if:

  • you've been feeling tired for a few weeks and you're not sure why
  • your tiredness affects your daily life
  • you feel tired and have other symptoms, such as weight loss or mood changes, or you've been told you're making gasping, snorting or choking noises when you're asleep

Treatment for tiredness or fatigue

Treatment for tiredness or fatigue depends on the cause.

Possible treatments include:

A GP may refer you to a specialist if they do not know the cause of your tiredness or fatigue.

You may need tests, such as blood tests to check for anaemia, diabetes or hyperthyroidism.

The information on this page has been adapted by NHS Wales from original content supplied by NHS UK NHS website nhs.uk
Last Updated: 18/06/2024 09:27:25