Fatigue is a lack of energy or weakness that differs from drowsiness. Fatigue will not go away with extra rest because it is usually the result of an underlying medical condition or treatment.
Cancer treatments like chemotherapy and radiation are known causes of fatigue. Because they are harsh on the body, your organs and cells need time to recover. Thus, fatigue makes you want to rest so you body can heal. However, this type of fatigue does not last too long and is perfectly normal.
Fatigue that continues on for a while may be the result of low blood counts leading to anemia. It's also possible that your thyroid was damaged during treatment. The thyroid helps with energy levels, so damage can result in fatigue. These and other causes are easily treatable, so talk to your doctor if you feel tired for an extended period of time post-treatment.
Fatigue that persists after cancer is in remission and your medical team rules out other treatable causes is called Post-Cancer Fatigue (PCF).
Though there is no known cause for PCF, you shouldn't worry, as it's normal. Your doctor should continue your regular check-ups to ensure everything is ok.
Fatigue can make it hard to function on a day-to-day basis. The best thing to do is to get adequate rest and think about your energy level. Prioritize your daily tasks so you use your energy on the most important ones. "Establish a new normal" by adjusting your schedule to match your energy.
Cancer Fatigue Resources
Photo by C. Leconte