Chemotherapy Side Effects See All Anemia and Chemotherapy in Chemotherapy Side Effects Chemotherapy can damage your body’s ability to make red blood cells, so body tissues don't get enough oxygen. This is a condition called anemia. People who have anemia may feel very weak or tired, dizzy, faint, or short of breath, or may feel that their hearts are beating very fast. ...more Hair Loss and Chemotherapy in Chemotherapy Side Effects People often choose to wear wigs, scarves, or hats while or after losing their hair.