Chemotherapy (keemo-thera-pee) is a treatment for cancer in which chemicals are used to destroy cancer cells. It is used primarily to treat cancers that can't be removed surgically, or to destroy cancer cells that remain after surgery. Chemotherapy is given either by mouth or by injection into a vein or muscle. The length and frequency of therapy depends on the type of cancer, the type of drugs used, and the body's response to them. Unfortunately, the anti-cancer drugs not only attack cancer cells, but may also damage normal cells. That is why chemotherapy often causes side effects such as nausea, vomiting, hair loss, fatigue, diarrhea, and low red and white blood cell counts. The side effects tend to vary with the amount and type of chemotherapy used. Although side effects are unpleasant, they will subside once treatment stops. Drugs may be given to control the side effects, and in some cases, the side effects may decrease as the body adjusts to the therapy. Depending on the type of cancer, chemotherapy is sometimes used in conjunction with surgery or radiation to increase the chance for a cure. For more information about chemotherapy, contact a healthcare professional.