Basics
Everyone reacts differently to the powerful chemotherapy drugs that are most effective for killing cancer cells. The drugs attack the fatal diseased cells but create side effects because they damage and kill healthy cells at the same time. According to the American Cancer Society, the organs most likely to be damaged by chemotherapy are hair follicle cells, bone marrow and blood cells and cells lining the digestive and reproductive tracts. There is no way to predict the exact nature of the side effects, although various chemotherapy drugs are more powerful than others and produce more lasting side effects. Factors such as the general health of the patient as well as the strength of the dosage all play a role in the level of damage.
Blood
Although most side effects of chemotherapy usually resolve themselves once the drugs are discontinued, there can be lasting side effects if the damage to blood cell counts isn't corrected. Patients must have blood taken regularly after chemo has begun to test red and white blood cell counts and platelets. Low white cell counts leave the body open to infection. Any signs of a fever, shortness of breath or redness near an injection site should be reported to the doctor. If an infection isn't caught in time, when the body's immunity is at low ebb, serious complications leading to death can occur. Low red blood cell counts, on the other hand, can lead to anemia and require a blood transfusion. Lasting side effects of blood transfusions include high blood pressure and a tendency to form blood clots, which can be life-threatening. Often, surgery must be delayed when platelet counts are low, which can seriously affect the patient's recovery time.
Heart
Hair grows back and appetite returns to normal when chemotherapy drugs are stopped. Unfortunately, some people experience damage to the heart that can't be corrected. About 10 percent of patients experience damage to the heart muscles, which can lead to congestive heart failure. Patients who have had previous heart problems, who smoke or have had radiation in the chest are most prone to heart difficulties following chemotherapy. Fluid builds up around the heart and causes symptoms such as swelling in the hands and feet, dizziness, dry cough, shortness of breath or erratic heartbeats. When doctors see signs of heart distress, they often stop the chemotherapy treatments early to prevent permanent heart damage.
