Chemotherapy (Drug Therapy for Cancer)

What is chemotherapy?

Chemotherapy is the use of medicines to control, slow, or cure medical conditions. The term chemotherapy is most often used to refer to the medicines given to slow or stop the growth of cancer cells. A problem with these medicines is that some of them also damage healthy cells.


The goals of chemotherapy are:

  • To cure the cancer with the fewest or least harmful side effects.
  • To control the cancer. This is done by keeping the cancer from spreading; slowing the cancer's growth; and killing cancer cells that may have spread to other parts of the body from the original tumor.
  • To relieve symptoms that the cancer may cause. Relieving symptoms such as pain can help people who have cancer live more comfortably.

What are the different types of drug therapy for cancer?

Chemotherapy uses many drugs. In general they fall into 3 categories:

  • antimitotic drugs
  • hormones and hormone inhibitors
  • biological therapy.

Most of the chemotherapy drugs are antimitotics. This means that they stop cancer cell growth by stopping cells from dividing into more cells. There are many ways that scientists have found to do this, so there are now many different kinds of these drugs. They include names you may have heard: Adriamycin (doxorubicin), Cytoxan (cyclophosphamide), and 5FU (5-fluorouracil.


Hormone therapy plays a very important role in chemotherapy. Sex hormone inhibitors are used to treat tumors that grow better with the hormones estrogen and testosterone. (These are hormones that naturally occur in the body.) The inhibitors stop the hormones from helping the tumor grow. Two commonly used hormone inhibitors are tamoxifen, which blocks female hormones in breast cancer, and finasteride, which blocks testosterone in men with prostate cancer. Hormones, such as cortisone (Prednisone), are also used to treat some tumors.


Biologic therapy, or immunotherapy, is a new name for a growing group of cancer drugs. They are medicines that help the immune system work better and fight the cancer. Interferon is an example of one of these drugs. Another example of biologic therapy is the use of antibodies. The goal is to identify or create antibodies that can bind to cancer cells. The antibodies can keep the cancer cells from multiplying, or they may destroy them. This type of therapy is also called biotherapy or biological response modifier therapy (BRM).

How is chemotherapy used?

Chemotherapy is used in several ways:

  • one drug alone
  • a combination of drugs
  • combined with surgery
  • combined with radiation
  • combined with both surgery and radiation.

The treatment depends on what type of tumor you have, where the tumor is, and how much it has spread. It can be given on many different schedules: daily, weekly, or monthly. The schedules are based on what research has found to work best for each type of cancer. The medicine can be given by mouth, by shot, or in tube put in a vein (IV, or intravenous). If given by shot, it can be injected into a muscle or it may be given into the spinal cord area.


IV medicine may be given over a few minutes or a few hours. You may be able to give some treatments to yourself at home. Portable pumps are available for chemotherapy treatments that go into the vein. The pump makes sure the prescribed dose of medicine is given over the correct period of time.

What side effects should I expect?

Common side effects of the antimitotics are fatigue, nausea, and hair loss. Other side effects depend on the drug, the dose, and your health. Examples of other possible side effects of these drugs are:

  • sores in your mouth
  • weight loss
  • lowered blood counts that make you more likely to get an infection.

An otherwise healthy person receiving chemotherapy may tolerate it very well. Someone who has several other serious medical problems in addition to cancer may have a more difficult time with side effects.


Common side effects from hormone inhibitors are symptoms of menopause for women taking the estrogen-blocking tamoxifen and lowered sex drive for men taking testosterone-blocking finasteride.


The biologic therapies (immunotherapies) often cause people to have flulike symptoms: fever, aches, chills, nausea, and loss of appetite.


Your health care provider will be watching closely for any side effects and help you manage them. If the side effects become severe, the dose of the drug may be lowered or the treatment may be postponed. Sometimes hospitalization is required for severe side effects. In extreme cases, treatment might be stopped.

What are clinical trials?

Ask your health care provider about clinical trials. These are studies being done to test new treatments, new medicines, and new combinations of medicines. Research programs sometimes allow you to receive the latest treatments. Ask your provider where the closest clinical trials are (often at universities and participating doctors' offices) and how you can learn more about them. Making an appointment to talk about a clinical trial does not mean you have to take part in the trial. The options, the risks, the costs, and whether your insurance will pay will be explained to you. Then you can decide if you want to join the study.

How should I take care of myself during treatment?

  • First, follow your health care provider's instructions for your treatment. Always ask questions to make sure you understand the directions. It is often helpful to have a friend or family member go with you to help you remember what is said at visits with your provider. You may want to take notes.
  • Be sure to tell your provider about all medicines, vitamins, supplements, and any alternative or complementary therapies you are using. Some of these might interact with your chemotherapy and cause more side effects.
  • Several doctors may be giving you care: your family health care provider, a cancer specialist (oncologist), a radiation oncologist (a doctor who specializes in the use of radiation for treatment), and a surgeon. Help your providers communicate with each other. Always take a list of your current medicines and chemotherapy drugs with you to ALL of your doctor visits, review the list with the doctor, and ask for the list to be included with your medical chart. Also share your test results from one provider's office with another by carrying copies of the results with you.
  • Get specific instructions about what to eat and drink and what to avoid.
  • Ask if you will need pain medicine and how to take it. If your cancer or your treatment is causing pain, it is usually best to take the pain medicine either on a regular basis or just when the pain is starting. There is usually no need to wait until the pain is severe.
  • Let trusted family members and friends help you. Give them specific suggestions for what they can do to help and make your life easier. They want to help.
  • Save your energy for important things and things you enjoy.
  • Laughter is the best medicine. Humor helps the immune system work. Read funny books or watch funny movies--whatever makes you laugh.

For more information visit the following Web sites:


You can also call:

  • American Cancer Society: 800-ACS-2345
  • National Cancer Institute: 800-4-CANCER.

Disclaimer: This content is reviewed periodically and is subject to change as new health information becomes available. The information provided is intended to be informative and educational and is not a replacement for professional medical evaluation, advice, diagnosis or treatment by a healthcare professional.


HIA File CNC3519F.HTM Release 9.0/2006

Copyright © 2006 McKesson Corporation and/or one of its subsidiaries. All Rights Reserved.

Copyright © 2006 McKesson Corporation and/or one of its subsidiaries. All Rights Reserved.