In brief
Feeling exhausted and having no energy. Everyday habits, health conditions and some medicines can all cause it.
- See your doctor if fatigue lasts more than 2 weeks and is not getting better, according to healthdirect.
- A blood test can check for anaemia, which is commonly caused by iron deficiency.
- Loud snoring with daytime sleepiness can be signs of sleep apnoea.
When to get help
Get help now
- You need urgent medical help: call triple zero (000).
See your doctor if
- Fatigue has lasted more than 2 weeks and is not getting better.
- It is worrying you.
- It is stopping you from doing things.
- It comes with other symptoms, such as weight loss.
Things that can contribute
- A busy schedule
- Lack of exercise
- Poor diet
- Poor sleep
- Too much caffeine
- Excessive alcohol use
- Other substance use
Questions you could ask your GP
- Could a blood test check for anaemia, iron levels or thyroid problems?
- Could any of my medicines be making me tired?
- Could my sleep, including snoring or sleep apnoea, be playing a part?
- Is my mood or stress level a factor here?
Based on healthdirect Australia, Fatigue. You can also check your symptoms with the healthdirect Symptom Checker, or speak with a registered nurse on 1800 022 222.
How it works
Fatigue is a feeling of tiredness that does not get better with rest. healthdirect lists common causes including a busy schedule, lack of exercise, poor diet, poor sleep, too much caffeine, and excessive alcohol or other substance use. Some medicines can cause fatigue too.
Health conditions linked with tiredness include anaemia, an underactive thyroid, sleep apnoea, depression and type 2 diabetes. Following the connections on the map shows how these link, but working out your own cause needs a conversation with your doctor.
Connections
13 connections on the map. Select a topic to read its page.
Tiredness and fatigue can be caused by
Poor sleep is a common cause of fatigue, according to healthdirect.
Source: healthdirect Australia, Fatigue
Feeling run down or tired during the day can be a symptom of depression.
Shift workers are often more tired during and after their shifts.
Source: healthdirect Australia, Sleep
Sleep apnoea causes daytime sleepiness.
Symptoms of type 2 diabetes can include feeling tired, hungry or thirsty.
Tiredness is a symptom of an underactive thyroid.
Source: healthdirect Australia, Hypothyroidism (underactive thyroid)
Anaemia may lead to fatigue and weakness.
Source: healthdirect Australia, Anaemia
Persistent mental and physical tiredness (fatigue) is a symptom of rheumatoid arthritis.
Source: Better Health Channel (Victorian Government), Rheumatoid arthritis
Tiredness and fatigue is linked with
Adrenal fatigue is not a recognised medical condition, according to healthdirect.
B12 deficiency can cause megaloblastic anaemia, which can make you feel tired or weak.
Source: NIH Office of Dietary Supplements, Vitamin B12 fact sheet for consumers
Tiredness is one sign of dehydration.
Source: healthdirect Australia, Drinking water and your health
Tiredness and fatigue can be eased by
Lack of exercise is a common cause of fatigue, according to healthdirect.
Source: healthdirect Australia, Fatigue
Sources
- Fatigue
- Anaemia
- Hypothyroidism (underactive thyroid)
- Obstructive sleep apnoea
- Depression
- Type 2 diabetes
Each connection above names its own source. See every source AskBioMap uses.
Causes and advice summarised from healthdirect. Sources read on 12, 13 and 16 October 2026. General education only, not medical advice. Spotted a mistake? Please tell us through the HuBu-Intel contact page.