Fatigue: 3 things to know about this cancer treatment side effect
December 08, 2025
Medically Reviewed | Last reviewed by Carmen Escalante, M.D., and Lucy Potter, M.D., on December 08, 2025
If you’re always feeling exhausted, you’re not alone. This is especially true if you just finished or are still undergoing cancer treatment.
“Fatigue is the most common side effect experienced by patients both during and after cancer treatment,” says internal medicine specialist Carmen Escalante, M.D.
But cancer-related fatigue tends to go undiagnosed, both because many patients are reluctant to discuss it and there’s no real way to test for it.
“There are no imaging studies or blood tests available to quantify fatigue,” explains Escalante. “So, when we evaluate patients for cancer-related fatigue, we have to consider many factors.”
The good news is that it’s still possible to reduce cancer-related fatigue. Escalante explored this topic in a recent Cancerwise podcast with internal medicine specialist Lucy Potter, M.D.
Here are three highlights from their discussion.
You don’t just have to accept cancer-related fatigue
Some patients don’t want to talk about cancer-related fatigue because they don’t want to complain. Others worry that if they tell their care teams about their fatigue, it could result in a change of medication, making their cancer treatment less effective.
“But don’t believe that fatigue is just a part of the package, and you have to accept it if you want optimal cancer treatment,” says Escalante. “Because that is not true. Fatigue is a legitimate side effect, and there are several things we can do to improve it. So, patients should definitely bring it up.”
Cancer-related fatigue can be treated
Physicians tend to focus on three main strategies when treating patients for cancer-related fatigue.
Exercise
This may sound counterintuitive, because the last thing we usually want to hear is that we need to get moving when we’re really tired.
“But the best data we have shows that both fatigue and quality of life improve significantly when people exercise regularly,” Escalante says. “It can also help with weight control, depression and anxiety. So, there are many benefits to exercising, even if you’re receiving cancer treatment.”
If you’re able, aim for at least 150 minutes of moderate exercise or 75 minutes of vigorous exercise per week. But start with what you can, as even small amounts of physical activity are beneficial during treatment.
Prioritizing tasks and activities
This means reviewing your daily or weekly activities and defining which ones are the most important to you. Which tasks must you absolutely complete, for example, and which ones can you delegate or put off indefinitely?
“Prioritization also means knowing what time of day you have the most energy, so you can take on your hardest tasks then,” adds Escalante.
Saving your energy for the most important activities
This means saving up your strength for the activities you really value. It also means finding ways to make them less strenuous.
“Many of my patients enjoy gardening,” explains Escalante. “But getting up and down from the ground can be very tiring. So, can you work on a raised garden, instead, or sit at a table and pot plants?”
Medications may also be an option
If nothing else works to relieve your cancer-related fatigue, your care team may consider stimulants. These are drugs that activate your central nervous system to make you feel more awake and alert.
“No stimulants have been approved by the Food and Drug Administration (FDA) specifically to treat cancer-related fatigue,” notes Escalante. “But for some patients, they can be very helpful. So, we sometimes use those off-label.”
Resources are available even after cancer treatment ends
Fatigue can last for months — or even years — after cancer treatment is finished. But if you’re still struggling with it, don’t despair. Help is available.
“We can’t guarantee that your fatigue will go away completely, but we can certainly get it to a more manageable level,” says Escalante. “We want patients to have the best quality of life possible.”
If you’re an MD Anderson patient, any member of your care team can refer you to our Cancer-Related Fatigue Clinic. You can also sign up for Active Living After Cancer, a no-cost, 12-week program designed for cancer survivors that involves physical activity, nutritional advice, and other activities that overlap with the recommendations our doctors often make to deal with cancer-related fatigue.
To hear the full discussion between Escalante and Potter, listen to the podcast.
Request an appointment at MD Anderson online or call 1-877-632-6789.