Chemotherapy drugs are powerful enough to kill rapidly growing cancer cells, but they also can harm perfectly healthy cells, causing side effects throughout the body.
Cancer cells divide more quickly than healthy cells, and chemotherapy drugs effectively target those cells. Unfortunately, fast-growing cells that are healthy can be damaged too. There are many different chemotherapy drugs with the potential for many different side effects. These effects vary from person to person and from treatment to treatment.
Factors that play a role in side effects include other ongoing treatments, previous health issues, age, and lifestyle. Some patients experience few side effects while others feel quite ill. Although most side effects clear up shortly after treatment ends, some may continue well after chemotherapy has ended, and some may never go away.
Chemotherapy drugs are most likely to affect cells in the digestive tract, hair follicles, bone marrow, mouth, and reproductive system. However, cells in any part of the body may be damaged.
Circulatory and Immune Systems
Routine blood count monitoring is a crucial part of chemotherapy. That’s because the drugs can harm cells in the bone marrow, where blood is produced. This can result in several problems. Red blood cells carry oxygen to tissues. Anemia occurs when your body doesn’t produce enough red blood cells, making you feel extremely fatigued. Other symptoms of anemia include:
- pale skin
- difficulty thinking
- feeling cold
- general weakness
Chemo can lower your white blood cell count, which results in neutropenia. White blood cells play an important role in the immune system: they help fight infection and ward off illness. Symptoms aren’t always obvious, but a low white blood cell count raises the risk of infection and illness. People with an immune system weakened by chemotherapy must take precautions to avoid exposure to viruses, bacteria, and other germs.
Cells called platelets help the blood clot. A low platelet count, called thrombocytopenia, means you’re likely to bruise and bleed easily. Symptoms include nosebleeds, blood in vomit or stools, and heavier-than-normal menstruation.
Some chemo drugs can weaken the heart muscle, resulting in cardiomyopathy, or disturb the heart rhythm, causing arrhythmia. This can affect the heart’s ability to pump blood effectively. Some chemo drugs can increase the risk of heart attack. These problems are less likely to occur if your heart is strong and healthy at the start of chemotherapy.