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Tired all the time panel - symptoms, diagnosis and treatment

Tired All the Time? Causes of fatigue, diagnostics blood tests and treatment.

The complaint of feeling tired all the time is unfortunately very common. It is so common in fact that, if I type the letters TATT into my system at work, the computer will automatically convert this to read ‘tired all the time’. It is a pervasive and sometimes debilitating complaint that may have a serious underlying cause or may have no obvious cause at all.


There are many things to think about for someone complaining of fatigue or being tired. Consideration should be given to the quality and quantity of sleep, to the general stresses and challenges of life, and a variety of medical conditions need to be checked for.

Sometimes, other symptoms are associated with the tiredness, and these may point to an underlying cause. A history of weight gain, or feeling cold all the time, may suggest that the problem is an underactive thyroid. Feeling thirsty all the time may suggest diabetes. Feeling breathless or light-headed might suggest that you are anaemic, or a history of unexplained weight loss and sweating heavily at night might point to more sinister causes such as blood cancers which would all be the cause of you being tired or chronically fatigued.

Our Tired All The Time blood test


The Tired All the Time Screen will help you exclude these as a cause of your fatigue or will allow you to receive the treatment that will make you feel better. Because tiredness can result from so many different conditions, this screen includes a large number of biomarkers.

Kidney, liver, vitamins?

However, there are often no other symptoms that point clearly to another problem. Conditions such as kidney disease and liver disease may cause no symptoms in their early stages apart from a general sense of malaise and lethargy. Nutritional deficiencies of vitamin B12, iron, folic acid or vitamin D may also just cause a lack of energy in their early stages.


To test for causes of tiredness you therefore have to cast quite a wide net to make sure you don’t miss anything. As you can tell from the above, a tiredness screen may pick up anything from an easily treated vitamin deficiency, to a life threatening illness.


But what if all the tests come back normal?


This is actually extremely common. The good news is that, because you have had such a battery of tests, you can be confident that your overall state of physical health is good. Despite this news, many people are very frustrated not to have an answer for the way they are feeling tired all the time. It's a hard problem and perhaps the cause does not lie in chemistry.


Other causes? Why am I tired all the time?

At this point other causes should be sought. One common cause of tiredness that won’t show up in blood tests is obstructive sleep apnoea. Sleep apnoea is a condition during which the sufferer continually stops breathing through the night. This sounds very dramatic but, in fact, the sufferer is usually completely unaware of it. 


What happens is that the muscles around the airway relax during sleep and the airway actually collapses. This causes the sufferer to stop breathing, so they come out of deep sleep, the airway opens up, and they drift off again. Although they may not awake fully, they spend the entire night in a half sleep and therefore are exhausted through the day, often falling asleep whilst watching TV, or sitting down after lunch, or travelling as a passenger in a car. Being tired all the time is no fun thing to go through. Sufferers almost invariably snore, and it is more common in people who are overweight because the extra weight around the neck makes the airway more liable to collapse.


Obstructive sleep apnoea is treatable, both with lifestyle and a medical intervention called Continuous Positive Airway Pressure, and this is usually very effective.

The other major cause of tiredness is stress and depression. In my opinion, this is by far the commonest cause for feeling tired and many people will recognise only that they feel tired, not that they feel low. The ICD-10 is an internationally used manual for the diagnosis of illnesses. It states that the three core symptoms of depression are low mood, loss of pleasure, and fatigue. Your doctor should consider a diagnosis of depression if just one of these core symptoms is present for longer than two weeks so, if all your blood tests for tiredness are normal, it is worth stepping back and considering if something in your life is making you unhappy.


No problem in medicine should be considered in isolation and being tired all the time is a worthy example. Everything we experience interacts with the broader aspects of our life and tiredness is a good example of this. Often, working out why you are feeling tired is not simply a matter of running blood tests. Instead, an overwhelming sense of fatigue should prompt you to look at your whole lifestyle and workout if there are changes to be made.

Our Ultimate Thyroid Function blood test


This is a complementary hormonal panel that often assists with the Tired All the Time investigation.


The Ultimate Thyroid Function Test checks for three different thyroid hormones which, taken together, give an accurate picture of the health of your thyroid and may even pick up an early problem before you have any symptoms.

Complexity of diagnosis

Diagnosing the cause of persistent fatigue, or "feeling tired all the time," can be complex because there are many potential causes. Fatigue is a common symptom that can be caused by a variety of physical, mental, and emotional factors, including:

  1. Medical Conditions: Fatigue can be a symptom of many medical conditions, including anemia, diabetes, heart disease, thyroid problems, and sleep disorders.

  2. Medications: Certain medications, such as anti-depressants, blood pressure medications, and pain medications, can cause fatigue as a side effect.

  3. Lifestyle Factors: Poor diet, lack of physical activity, stress, and lack of sleep can all contribute to fatigue.

  4. Psychological Factors: Depression, anxiety, and other mental health conditions can cause fatigue.

  5. Chronic Fatigue Syndrome: This is a condition that is characterized by persistent and unexplained fatigue, which can last for months or even years.

Given the wide range of potential causes, diagnosing the cause of fatigue can be complex and may involve multiple tests and evaluations. A thorough medical evaluation, including a review of the person's medical history, physical examination, and laboratory tests, may be necessary to determine the underlying cause of fatigue. In some cases, referral to a specialist, such as a sleep specialist or a mental health specialist, may also be necessary.

It is important to note that fatigue is a common symptom, and in many cases, it can be managed with simple lifestyle changes, such as getting adequate sleep, eating a balanced diet, and engaging in regular physical activity. However, in some cases, fatigue may be a symptom of a more serious underlying condition, and prompt medical evaluation is recommended.

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