About this symptom
Tiredness, or fatigue, is a feeling of weariness or low energy. It is different from drowsiness, which is the need to sleep. It is a symptom, not a disease.
Almost everyone feels tired after a bad night, hard work or a stressful time, and this passes. Tiredness that does not improve with rest, good food and less stress, or that goes on for weeks, is worth checking. A cause can often be found with a few simple tests.
Possible causes
This is not a diagnosis. These are the causes doctors think about, with the ones that are most urgent to rule out first.
- Heart failureTiredness with swollen feet, ankles or legs, sudden weight gain, and breathlessness that is worse on effort or lying down.Read about it
- Iron deficiency anaemiaLow energy with pale skin, breathlessness and a pounding heartbeat. Heavy periods and bleeding in the stomach or bowel are common causes.Read about it
- Type 2 diabetesTiredness with constant thirst, passing urine more often (especially at night) and weight loss.Read about it
- Underactive thyroidTiredness with constipation, dry skin, weight gain and feeling the cold more than other people.Read about it
- Overactive thyroidTiredness with restlessness, nervousness, irritability and muscle weakness.Read about it
- Sleep apnoeaTiredness through the day, with loud snoring and gasping, snorting or choking noises in sleep that other people notice.Read about it
- DepressionTiredness with feeling sad or low, and trouble sleeping.Read about it
- Poor sleep or stressThe commonest causes. Tiredness that follows late nights, long working hours or a stressful time, and eases as these settle.
When to get help
See a doctor soon if you have:
- Tired for a few weeks and not sure why, or tiredness that affects your daily life
- Tiredness with weight loss, fever or night sweats
- Tiredness with pale skin, breathlessness on mild effort or a pounding heartbeat
- Tiredness with constant thirst and passing urine more often
- Tiredness with swollen feet or ankles and sudden weight gain: see a doctor within a day or two
- Feeling low or sad, trouble sleeping, or loud snoring with gasping at night
If your tiredness follows a poor night, a busy spell or a stressful time, is easing, and none of these signs apply, it can wait. See a doctor if it lasts a few weeks.
What you can do at home
Do
- Keep regular sleep and wake times, and aim for 6 to 9 hours of sleep
- Eat a balanced diet, drink water through the day and be active most days
- Wind down before bed, in a calm, quiet, cool, low-light bedroom
- Try relaxation such as yoga or meditation to ease stress
Do not
- Do not rely on caffeine or sleeping tablets to keep going
- Do not smoke or drink much alcohol
- Do not eat, drink caffeine or exercise in the couple of hours before bed, or use a phone in the last hour
- Do not start vitamin tablets on your own, or stop a medicine you think is causing it, without asking a doctor
What the doctor will do
The doctor will ask how long you have been tired, how it affects your day, how you sleep and eat, your mood, stress, alcohol, and the medicines you take. They will examine you, including your heart, glands, thyroid, tummy and nerves.
They may order tests, depending on what they find:
- Blood tests for anaemia, diabetes, infection and inflammation
- Kidney, liver and thyroid blood tests
- A urine test
Treatment depends on the cause. It may include advice on sleep, relaxation or lifestyle, talking therapy, or a referral to a specialist if the cause is still not clear.
Myths and facts
Things people often say about this. Open each one to see what is true.
Myth“Tiredness means I need an iron or vitamin tonic.”What is true?
Fact
Tiredness has many possible causes, including anaemia, diabetes and thyroid problems, and a blood test can show which one. Ask a doctor whether vitamin supplements would help before you start them.
Myth“Strong tea or coffee will cure tiredness.”What is true?
Fact
Caffeine and other stimulants do not treat tiredness, and they can make it worse when you stop. Better sleep, regular meals, activity and treating the cause work better.
Myth“Being tired is just part of life, so there is no need to see a doctor.”What is true?
Fact
Many people put up with it, but tiredness that lasts a few weeks or affects daily life is worth checking at any age. Conditions such as anaemia, diabetes and an underactive or overactive thyroid can cause it, and they can be treated.
Questions to ask your doctor
Tick the ones you want answered and take them with you.
Common questions
How long is it normal to feel tired?
Tiredness after a poor night's sleep, hard work or a stressful time is common and usually passes. If you have been tired for a few weeks and do not know why, or it affects your daily life, see a doctor.
Can stress or low mood make me tired?
Yes. Stress, low mood, and life events such as a bereavement or caring for a new baby are common causes of tiredness. If low mood is part of it, tell your doctor, because help is available.
Which tests find the cause of tiredness?
Often a few blood tests are enough, for anaemia, diabetes, thyroid problems, and kidney or liver problems. A urine test may be added. The doctor chooses tests after asking about your sleep, mood, medicines and other symptoms.
Can my medicines make me tired?
Yes. Some medicines for allergies, blood pressure, depression and sleep can cause tiredness. Do not stop or change a medicine yourself: tell your doctor, who can adjust it if needed.
