Fatigue is a daily lack of energy or whole-body tiredness that doesn’t go away, even with good sleep. It can keep you from doing normal, daily things, and it affects your quality of life. Sometimes it's "acute," meaning it lasts a month or less. In other cases it's "chronic" and lasts up to 6 months or longer. Usually, it comes on suddenly, and may continue after you're done with your treatment.
Here are some possible reasons for it, along with tips to help you get some of your energy back.
Causes of Cancer-Related Fatigue
The disease itself can be the problem. Tumor cells steal calories and nutrients from normal cells, and that leads to tiredness that won't seem to let up.