Fatigue can also affect the way you think and feel. It can cause you to lose interest in your hobbies, make concentrating on school or work difficult, and lead to social withdrawal. Some days, I don t even want to play with my children. Chemotherapy can lower the number of red cells, which carry energy-providing oxygen throughout your body. Patients who have nausea or vomiting may not eat enough to keep up energy levels.
Cranial radiation can also cause fatigue.
Studies have shown that patients generally describe fatigue as minimal at the beginning of radiation therapy, but that it increases as radiation therapy progresses. Many patients experience debilitating tiredness as long as 3 months after completion of radiation therapy. Somnolence syndrome, a short term but distressing event, has been observed in a smaller percentage of patients with brain tumors, and occurs most commonly 4 to 8 weeks following radiation to the brain. Its symptoms can range from mild fatigue to drowsiness, to sleeping up to 20 hours per day. It can be accompanied by headache, vomiting, anorexia, and depression.