Tiredness can be defined as a lack of energy, feeling weak, or being too tired to participate in family, work, or leisure activities.(1)

We all experience tiredness or fatigue from time to time, whether it’s from a long workday, a day full of chores or a day spent running after screaming toddlers. However, sometimes we may find ourselves feeling unusually tired for periods of time with no discernible cause. We may consequently struggle to concentrate on day-to-day activities, have a low mood and feel rather sleepy.

If you are experiencing unexplained tiredness, know that you are not alone. Feeling tired/run down is one of the top three reasons for seeing a GP, and around 80 to 85% of the time, the cause will become apparent to your GP by the end of the consultation.(2,3)

While tiredness is a common symptom of several medical conditions and some serious diseases, most of the time, the cause is easy to identify and manage. This article will briefly review some of the leading causes of tiredness, covering lifestyle, physical and psychological factors.


POOR SLEEP. Adults should be aiming to get at least 6 to 9 hours of sleep a day. Inadequate sleep will not only make you tired but can affect your ability to eat well and exercise, which can further perpetuate tiredness.

ALCOHOL. A high alcohol intake can upset sleep. Current guidelines recommended that adults adhere to no more than 14 units of alcohol a week.

CAFFEINE. While caffeine (commonly found in tea, coffee and energy drinks) can increase energy in the short term, a high caffeine intake can affect sleep and make you agitated as well as tired. You can try slowly decreasing the intake of caffeinated fluids or trying decaffeinated drinks.

Other lifestyle causes include skipping meals, a sedentary lifestyle and night shifts.


ANAEMIA. Anaemia is a condition where your body lacks enough healthy red blood cells to carry oxygen to your body’s tissue, making you feel tired and weak. Your GP can check for anaemia with a routine blood test.

UNDERACTIVE THYROID (HYPOTHYROIDISM). An underactive thyroid is when thyroid hormone production is deficient in the body, which can cause you to feel tired, gain weight and feel depressed. Your GP may prescribe daily hormone tablets if you have an underactive thyroid. 

SLEEP APNOEA. The most common type is obstructive sleep apnoea which is when your breathing stops and starts while you sleep. Sleep apnoea may cause you to wake up several times during the night which severely impacts your sleep quality.

As tiredness is a non-specific symptom, there is a never-ending list of medical conditions resulting in tiredness. These include endocrine and metabolic causes such as pregnancy and diabetes; heart and lung conditions such as asthma and coronary heart disease and side effects of everyday medications such as antihypertensives.

To find out more about medical causes please speak to one of our GPs or visit our website www.gogodoc.com


STRESS. Long-term or chronic stress can affect us both physically and mentally. There are various strategies to help you deal with stress, including physical exercise, time-management techniques, and talking to family members, friends, or healthcare professionals.

DEPRESSION. Feeling depressed can lower your energy and reduce your sleep quality, making you feel tired. By speaking to your GP, you can discuss treatment options, including medication or talking therapies. To find more about depression and book an appointment visit our page: https://gogodoc.com/depression-gp-appointment/

ANXIETY. A common type of anxiety known as generalised anxiety disorder (GAD) is where you experience constant and uncontrollable anxiety, affecting your day-to-day activities. Find out more about anxiety here https://gogodoc.com/anxiety-gp-appointment/


There is no straightforward method to distinguish between normal and abnormal tiredness, and at times there may be multiple factors that contribute to feeling tired or fatigued. If you are experiencing an unusual amount of tiredness, please do not hesitate to contact one of our GPs. They will be more than happy to discuss your situation and provide guidance.


  1. Nicholson K, Stewart M, Thind A. Examining the symptom of fatigue in primary care: a comparative study using electronic medical records. JOURNAL OF INNOVATION IN HEALTH INFORMATICS [Internet]. 2015;22(1). Available from: http://dx.doi.org/10.14236/jhi.v22i1.91
  2. McAteer A, Elliott AM, Hannaford PC. Ascertaining the size of the symptom iceberg in a UK-wide community-based survey. British Journal of General Practice [Internet]. 2011 Jan [cited 2021 Feb 8];61(582). Available from: https://pubmed.ncbi.nlm.nih.gov/21401979/
  3. Tired All The Time (TATT) – General Practice Notebook [Internet]. 2018 [cited 2021 Feb 8]. Available from: https://gpnotebook.com/simplepage.cfm?ID=x20190411125959960611
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