Chemotherapy has to be planned carefully. It’s usually given as a series of sessions of treatment. Each session destroys some of the cancer cells and will cause some damage to healthy cells. After each treatment, there’s usually a rest period to allow the healthy cells to recover before the next dose. A session of chemotherapy and the rest period is known as a cycle of treatment. A series of cycles make up a course of treatment.
There are many different ways of giving chemotherapy. Sometimes, high doses of the drugs are given intensively over a short period of time, or they may be given as lower doses over a longer period.