The term chemotherapy refers to treating cancer with drugs. A drug, or combination of drugs, is administered by injection into a vein. Chemotherapy is often used to treat prostate cancers that are resistant to hormonal treatments. A single drug or a combination of drugs may be used, depending on the type and stage of cancer.

After the first round of chemotherapy, most men receive further doses on an outpatient basis at a clinic or physician's office. Side effects depend on the drug used and the frequency and duration of the treatment. Although these drugs can be very effective in terms of destroying cancer cells, they can also harm normal cells that divide rapidly. For this reason, the side effects of chemotherapy can be somewhat severe. However, these side effects will gradually lessen after the chemotherapy is completed.