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Beyond tired of COVID? Discover underlying issues that may be causing your fatigue after COVID

April 18, 2023

There are a growing number of tired people looking for answers: 25% of people who had COVID-19 develop post-acute syndrome of COVID-19 (PASC; long COVID, post COVID, long-haul COVID), which can often present as chronic fatigue among other symptoms. If you’re experiencing persistent fatigue for more than four weeks after having been diagnosed with COVID, you may be experiencing long COVID and want to understand whether your tiredness could be caused by COVID or something else. 


Here are three ways to get answers and start discovering what may be causing your fatigue.

Understand long COVID symptoms and how common they are

Sometimes referred to as “post-COVID conditions,” long COVID is less of a disease and more of a collection of ongoing health symptoms as a result of having been infected with the SARS CoV-2 virus. These symptoms can last weeks, months or even years and are found most often in people who had a more severe case of COVID-19. However, anyone infected can experience long COVID.

Just like COVID-19 itself, long COVID symptoms vary from person to person. These symptoms may include but are not limited to:

  • Tiredness or fatigue that interferes with daily life
  • Fever
  • Cough and difficulty breathing
  • Headache
  • Dizziness
  • Difficulty thinking or concentrating (sometimes referred to as “brain fog”)
  • Sleep problems
  • Stomach pain
  • Rash
  • Persistent loss of smell and/or taste
  • Joint pain; muscle aches and pain/weakness

Having fatigue—extreme tiredness that gets in the way of your daily life—could mean a number of health-related issues that need addressing. There is no single test that can diagnose long COVID, but providers can diagnose it by ruling out other possible causes.

Take health tests to help understand what may be causing your fatigue symptoms

Long COVID is just one of many health conditions that could be causing your fatigue, and it is important to get to the bottom of what is contributing to your fatigue. From low iron to overall lifestyle habits, the list of reasons you may be experiencing fatigue is long.

There are several tests and screenings, however, that can help narrow down the underlying medical conditions that may be causing your fatigue:

  • Complete Blood Count (CBC). This test counts the cells that circulate in your blood, which provides valuable insight for you and your healthcare provider. This test can be a first step in detecting fatigue-causing conditions, such as anemia
  • Comprehensive Metabolic Panel (CMP). This blood test measures essential components in your blood—sugars, minerals, electrolytes, enzymes and even waste products. Your healthcare provider can use these results along with a clinical examination to help detect certain health conditions that can cause extreme fatigue
  • Ferritin. This test measures your levels of ferritin, a protein that stores iron in your cells. When your iron levels are too low, your body cannot make the red blood cells it needs, causing anemia. Extreme fatigue is a common symptom of anemia.

Results from tests like these help you and your healthcare provider gain insight on what might be causing your fatigue. Testing can help you and your provider figure out treatment options to get you feeling more rested and energetic.

Take a comprehensive fatigue test and discuss your results

Because fatigue as a symptom is attached to so many illnesses, diseases and conditions, it may take patience and trial and error to figure out if it’s long COVID or not. Some tests may help you gain a clearer picture of what’s causing your fatigue—a comprehensive fatigue test may get you even closer.

If your fatigue persists for more than six months, and it does not improve with rest, it’s time for answers. The Fatigue Test from Labcorp OnDemand can help shed light on potential health imbalances and deficiencies.

While there is no test to diagnose long COVID, the Fatigue Test can provide information about critical health measures that may be contributing to your fatigue. It’s important to share and discuss your results with your healthcare provider. Let them know exactly how you feel, how the fatigue interferes with your daily life, and any other symptoms you may be experiencing. 

Having conversations about your symptoms and your test results with your provider are powerful tools—use them to take control of your fatigue and help get back to a more well-rested life.