Advanced Tiredness and Fatigue Blood Test, from our experts to you.
Dr Natasha Fernando MBBS, MRCGPMedical Director

What is the Advanced Tiredness and Fatigue Blood Test?
Feeling tired is one of the most common reasons people visit their doctor, but sometimes finding out the reasons for your symptoms can be a journey of trial and error. Often, fatigue is caused by anaemia, either from iron deficiency or low levels of B vitamins, which are essential to creating normal red blood cells.
Our Advanced Tiredness and Fatigue Blood Test includes all of the tests in our Tiredness and Fatigue Blood Test plus a full blood count (FBC), where we look at the number, size, and shape of your red blood cells. If your red blood cells are abnormal, it affects their ability to transport oxygen around your body, a common cause of fatigue.
What can I learn from this test?
Our advanced fatigue profile aims to get to the cause of low energy levels. With it, you can check your iron status and active vitamin B12 levels, your red blood cells to make sure that they show no signs of anaemia, and white blood cells to check that infection or inflammation is not contributing to your symptoms. We also check for vitamin D deficiency, which is a very common cause of low energy and aches and pains and other causes of fatigue like diabetes and an underactive thyroid.
What can I learn from this test?
As this is an advanced test with added markers, your blood sample will be taken from a vein in your arm (a venous sample) rather than collected from a finger-prick collection. You can choose a nurse to collect your sample from you at home or at one of our clinics, or you can make your own arrangements. A venous blood test allows us to check more markers and include an FBC, where we look at the number, size, and shape of your red blood cells.
What's Included?
How to prepare for your test
Special Instructions
Prepare for your Advanced Tiredness and Fatigue Blood Test by following these instructions. Please take your sample before 10am. Take this test when any symptoms of short-term illness have settled. You should take this test before you take any medication or vitamin/mineral supplements. Do not take biotin supplements for two days before this test, discuss this with your doctor if it is prescribed. Do not take vitamin B12 for two weeks prior to this test. If your B12 is prescribed ask your doctor whether to stop.