Why did my cancer treatment make me so tired?

This is called Cancer Related Fatigue or CRF, and is now a recognized condition. It can persist for months to years after completing treatment.

Fatigue is probably the most common complaint of cancer and its treatments. It has been attributed to many different factors, and is a subject of ongoing research.

Chemotherapy causes anemia (low RBCs or Hb), and it was popular to aggressively treat it with injections to stimulate RBC production. (Erythropoietin). Unfortunately, that didn’t really eliminate, or even significantly decrease fatigue, and even causes adverse reactions in some cases. We have backed off using these agents in curative situations, and reserve their use to specific conditions.

Radiation of the neck can cause low thyroid gland function. This can be measured and supplemented with pills.

Lack of exercise, and deconditioning can make fatigue worse. Keeping up with moderate amount of exercise can help with conditioning. Exercise increases brain production of endorphins, which help you feel better.

Anxiety and depression can interfere with brain chemistry, disrupt sleep patterns, and general functioning. Good support systems, therapy and medication can help.

Poor nutrition and hydration, both quality and quantity will not help the body heal. Sometimes, a nutrition consult will help keep you on track.

Good sleep habits are essential to help the body heal. Sleep issues are endemic to our modern world, with non-stop electronic stimulation and irregular hours. Minimizing, even eliminating caffeinated drinks, a regular bedtime, turning off the TV at least an hour before bedtime, a quiet and dark bedroom, and relaxation exercises will all help.

There is a new study, which has found the presence of markers of inflammation (C-reactive protein, or CRP) correlating with the level of fatigue. Research is ongoing, whether using anti-inflammatory agents will help reduce fatigue.

Another recent study showed the benefit of active intervention addressing the issues of nutrition, sleep, anxiety, depression and exercise decreased the level of fatigue, as compared to no intervention.

With all that, there are many other internal reactions that chemotherapy may be producing, that cause fatigue. I once had to take one small dose of a very mild drug called Methotrexate. I was exhausted for several days, and was convinced that my blood counts had plummeted. I got a blood test, and they were fine. There was no other explanation for my fatigue. Since then, I am even more appreciative of how valiantly my patients go through treatment, and continue working, and taking care of their families.