Fatigue is one of the most common reasons people see a GP, and one of the most commonly dismissed — often by the person experiencing it. The useful distinction is not how tired you are, but whether rest fixes it.
When tiredness is worth investigating
Ordinary tiredness responds to rest. If you sleep properly for a week or two and feel better, that is life — a new baby, a hard stretch at work, a rough winter.
Fatigue worth investigating looks different. It persists despite adequate sleep, it is disproportionate to what you have been doing, and it interferes with things you would normally manage without thinking.
Book an appointment if
- You have been tired for more than a few weeks despite sleeping reasonably.
- You are short of breath on stairs you used to manage.
- Your heart races or you feel dizzy when you stand up.
- You are bruising easily, or bleeding more than usual.
- You have lost weight without trying.
- You have night sweats, fevers, or pain that wakes you.
- Your periods are heavy, or you have noticed blood in your stool.
- You have stopped enjoying things, or the tiredness comes with low mood.
That last one matters. Fatigue and depression overlap heavily, and it is genuinely difficult to tell from the inside which is driving which. Both are worth assessing. See mental health care.
What we usually test
There is no single “tiredness test”, but there is a sensible first round. What your GP orders depends on your age, sex, history and what they find on examination — the list below is the sort of thing that is commonly included, not a menu to pick from.
- Full blood count — looking for anaemia and other blood abnormalities.
- Iron studies, including ferritin — iron deficiency is one of the most common treatable causes, particularly in women with heavy periods and in people who do not eat meat.
- Thyroid function — an underactive thyroid causes fatigue, weight change, cold intolerance and low mood, and it is easily treated.
- Blood glucose or HbA1c — undiagnosed diabetes often presents as tiredness and thirst.
- Kidney and liver function, and electrolytes.
- Vitamin B12 and vitamin D where the history suggests it.
- Coeliac screening where there are bowel symptoms, iron deficiency or a family history.
- Inflammatory markers where an inflammatory or infectious cause is possible.
Bloods are collected on site through 4Cyte Pathology, so the tests ordered at your appointment can usually be done before you leave rather than requiring another trip. See pathology and blood tests.
The common causes
Most persistent fatigue turns out to have an explanation, and often more than one at once.
- Iron deficiency, with or without anaemia. Very common, very treatable — and the important part is working out why the iron is low, not just replacing it.
- Thyroid problems. Straightforward to test and to treat.
- Sleep apnoea. Suspect it if you snore, wake unrefreshed, or fall asleep in the afternoon. It is under-diagnosed and it does real cardiovascular damage over time.
- Depression and anxiety. Fatigue is often the first symptom people notice and the last they attribute to mood.
- Medicines. Blood pressure tablets, antihistamines, some antidepressants and others can all contribute. Worth reviewing.
- Alcohol. It fragments sleep even when it helps you fall asleep. An honest number here is genuinely useful.
- Post-viral fatigue. Common after significant infections, and usually improving over weeks to months — but worth reviewing if it is not.
- Chronic conditions including diabetes, kidney disease, heart failure, coeliac disease and inflammatory conditions.
In adults, some causes of iron deficiency need ruling out properly, including bleeding from the bowel. If your GP suggests further investigation, it is not because they suspect the worst — it is because iron deficiency is a symptom and the cause matters.
What to bring to the appointment
- How long it has been going on, and whether it came on suddenly or gradually.
- What your sleep is actually like — when you go to bed, how long to fall asleep, whether you wake, whether you snore, how you feel on waking.
- Your medicines and supplements, including anything from the chemist.
- How much alcohol, in standard drinks per week.
- Any other symptoms, even if they seem unrelated.
- Your family history of thyroid disease, coeliac disease, diabetes and blood conditions.
Book a longer appointment if you can. Fatigue is a proper history-taking conversation, not something to squeeze into the last two minutes of a consultation about something else.
Things worth doing regardless
While the investigation runs, these are the changes that make the biggest difference to how tired people feel — and they are also the ones that make the results easier to interpret.
- A consistent wake time, seven days a week. It anchors sleep more effectively than a consistent bedtime.
- Daylight in the first hour of the day, and less screen light in the last.
- Movement, even a walk. Exercise reliably reduces fatigue, which feels counterintuitive and is well established.
- Less alcohol, particularly in the evening.
- Eating actual meals. Skipping breakfast and running on coffee until two in the afternoon has predictable results.
If none of that shifts it, that is useful information too. Bring it back to your GP.
This article is general information for people in the Gosford and Central Coast area. It is not advice about your situation and it does not replace a consultation with your own doctor. If you are worried about a symptom, book an appointment or call us on (02) 4311 3800. In an emergency, call 000.
Back to the Health Journal