Fatigue is a symptom that varies from person to person and can't easily be seen from the outside. It's a common symptom in people diagnosed with mitochondrial disease (mito) and can impact day-to-day life. Doctors can do tests to find out what might be contributing to your fatigue and refer you to other specialists as needed.  There are things you can do to help manage fatigue including looking after your physical and mental health. 1,2

Download the Fatigue and Mito information sheet for more information and practical tips.

Fatigue affects people in different ways and is mostly an invisible symptom. It is often described as feeling sleepy, weak, exhausted or brain fog, making it hard to do physical activities or think clearly. But, unlike tiredness, fatigue does not always go away with rest.

How the mito community describe their fatigue:

"It's the loneliest feeling in the world."

Mito Community Member, 2022


"I find myself feeling frustrated or isolated emotionally in that I can't expect others to understand or relate, yet I wish they did."

Mito Community Member, 2022


Fatigue is something that might be experienced after physical activity, but it can also be caused by different medical conditions, such as mitochondrial disease (mito). Many neurological conditions are linked to fatigue, and it's a common symptom of mito. While fatigue affects individuals differently, it can be particularly debilitating for some. In fact, a significant number of people find fatigue to have a long-lasting impact on their daily lives, lasting for more than six months. 2, 3

Discover more about fatigue, including how it's measured and how common it is, by watching Dr Christina Liang's presentation at the 2022 AussieMit Community Summit.


Symptoms of fatigue

Fatigue can be associated with the following symptoms:


What can cause fatigue?

Whilst the exact cause of fatigue is unclear, several factors can influence fatigue. It's important to understand these factors to address fatigue and its related symptoms.

Primary factors are directly linked to the disease process. In mito, the energy production in cells is affected. This can lead to difficulties in exercising and feeling fatigued. Problems in other body systems due to mito can contribute to sleep disorders, further intensifying feelings of fatigue.

Secondary factors are associated with lifestyle choices, stressors, and psychological factors. By minimising these factors, the overall quality of life for a person can be improved.

  • Not getting enough or getting too much sleep can make you feel fatigued.
  • Drinking alcohol slows down your body's systems and can disrupt your sleep.
  • Smoking cigarettes and consuming caffeine can make it hard to fall asleep or stay asleep.
  • A lack of exercise can make you feel fatigued. Regular, modified exercise can help you feel better, reduces stress, and gives you more energy.
  • A poor diet that lacks good nutrition can worsen mitochondrial function by not giving your body enough fuel and essential nutrients.
Fatigue info sheet image

What tests will my doctor do to find out what's causing my fatigue?

The tests your health professional may carry out vary depending on the potential causes of your fatigue. 

These tests may include:

This involves finding and reducing things that might be damaging your mitochondria, like certain medications, dehydration, or eating a lot of processed foods. Read more about Nutrition and Mito.

What can I do to reduce fatigue?

Watch Dr Christina Liang discuss managing fatigue.


Stress uses a lot of energy. So introducing relaxing activities into your days, such as listening to music, reading or spending time with family and friends, may help.

Hear from Registered Psychologist and Mito Community member Shelley Beverley discuss the importance of well-being and maintaining a quality of life while living with mito.

Useful links


1. Torri F, Lopriore P, Montano V, Siciliano G, Mancuso M, Ricci G. Pathophysiology and Management of Fatigue in Neuromuscular Diseases. International Journal of Molecular Sciences [Internet]. 2023; 24(5).
2. Sue CM, Balasubramaniam S, Bratkovic D, Bonifant C, Christodoulou J, Coman D, et al. Patient care standards for primary mitochondrial disease in Australia: an Australian adaptation of the Mitochondrial Medicine Society recommendations. Internal Medicine Journal. 2022;52(1):110-20.
3. Gorman GS, Elson JL, Newman J, Payne B, McFarland R, Newton JL, et al. Perceived fatigue is highly prevalent and debilitating in patients with mitochondrial disease. Neuromuscular Disorders. 2015;25(7):563-6.
4. Rush IR. What are the Physical Symptoms of Grief? 2022 [Available from:
5. Carney CE. 11 Ways to Fight Fatigue 2015 [Available from:
6. Strand E. Fighting Fatigue with Diet 2016 [Available from: