Also known as: Cancer chemotherapy, Cancer drug therapy or Cytotoxic chemotherapy


Chemotherapy is the use of drugs to kill bacteria, viruses, fungi, and cancer cells. Most commonly, the term is used to refer to cancer-killing drugs. This article focuses on cancer chemotherapy.

The goal of chemotherapy is to:The correct answer is all of the above. Chemotherapy refers to cancer-killing medicines. These medicines can sometimes offer a cure. But even in incurable cases, chemotherapy can help slow the spread of cancer and relieve symptoms.Chemotherapy is the best treatment for all forms of cancer.The correct answer is false. Doctors often treat early-stage cancer without chemotherapy. Surgery followed by radiation therapy is standard for many early-stage cancers, including breast cancer. Your oncologist will recommend a treatment strategy based on the type and stage of your cancer.Chemotherapy is given by:The correct answer is any of the above. How you receive chemotherapy depends on the type of cancer and where it is found. If you need chemotherapy for a long period of time, doctors can put a thin catheter, called a central line, into a large vein. The catheter stays in place throughout treatment to make it easier to deliver the medicine.Chemotherapy is usually given in cycles.The correct answer is true. Chemotherapy is most often given in cycles. These cycles may last one day, several days, a few weeks, or more. There will usually be a rest period with no chemotherapy between each cycle. A rest period may last for days, weeks, or months. This allows your body to recover before the next dose.Taking vitamins and dietary supplements during chemotherapy:The correct answer is that supplements may be OK if you check with your doctor. Some vitamins, minerals, or herbs may change how chemotherapy affects your body. Make a list of any supplements you want to take and discuss it with your doctor.Besides attacking cancer cells, chemotherapy may damage healthy cells in the:The correct answer is all of the above. Chemotherapy medicines travel throughout your entire body. This means they may damage or kill some normal cells. Depending on which cells are damaged, side effects may include hair loss, nausea, anemia, fatigue, and greater risk of infection.If you lose your hair during chemotherapy, it will never grow back.The correct answer is false. If you lose your hair, it will most likely grow back 2 to 3 months after you finish chemotherapy. But it may not look the same as your old hair. It may have a different texture or color. Losing your hair can be difficult. Talk with your doctor about ways to deal with hair loss.To cope with a poor appetite during chemotherapy:The correct answer is eat 5 or 6 small meals a day. Get the most out of each small meal by eating foods that are high in calories and protein. Set a schedule for your meals and eat even if you aren't hungry. Eating well helps your body fight your cancer.To prevent infections during or soon after chemotherapy:The correct answer is E, all of the above. Chemotherapy can make you more vulnerable to infection. Protect yourself by avoiding raw foods, unsanitary water, and crowds. Wash your hands with soap and water often, especially after handling food or doing housework.It's impossible to work while receiving chemotherapy.The correct answer is false. Many people continue working during chemotherapy. It helps if you can work from home or take a day off when your energy is low. State or federal laws may require your employer to let you adjust your work schedule during chemotherapy.


Chemotherapy drugs can be given by mouth or injection. Because the medicines travel through the bloodstream to the entire body, the majority of administered chemotherapy is considered a body-wide (systemic) treatment.

Chemotherapy may be used to:

  • Cure the cancer
  • Keep the cancer from spreading
  • Ease symptoms (when the cancer cannot be cured)


Depending on the type of cancer and where it is found, chemotherapy may be given in a number of different ways, including:

  • Injections or shots into the muscles (intramuscular, or IM) or under the skin (subcutaneous, or SC)
  • Into a vein (intravenous, or IV)
  • Into an artery (intra-arterial)
  • Pills taken by mouth (PO)
  • Shots into the fluid around the spinal cord or brain (intrathecal, or IT)

Different chemotherapy drugs may be given at the same time in combination or after each other in sequence. Patients may receive radiation therapy before, after, or while they are getting chemotherapy. 

Chemotherapy is most often given in cycles. These cycles may last one day, several days, or a few weeks or more. There will usually be a rest period when no chemotherapy is given between each cycle. A rest period may last for days, weeks, or months and is given in order for the body and blood counts to recover before the next dose.

Often, the chemotherapy is given at a special clinic or at the hospital. Some people are able to receive chemotherapy in their home, even when the chemotherapy is given into the veins. Patients and their family members will receive special training if this is planned.

When chemotherapy is given over a longer period of time, a thin catheter can be placed into a large vein near the heart. The catheter is placed during a minor surgical procedure. This is called a central line (there are many types, including ports) or a percutaneously inserted central catheter (PICC).


Traditional chemotherapy medicines work best on cells that divide often to make new cells. This is typical of most cancer cells.

However, some normal cells -- including those found in the bone marrow, hair, and the lining of the gastrointestinal tract -- also divide very quickly. Chemotherapy can also damage or kill these healthy cells.

When this damage occurs, there can be side effects. Some people who receive chemotherapy:

Side effects of chemotherapy depend on many things, including the type of cancer, and which drugs are being used. Each patient reacts differently to these drugs. Some newer chemotherapy drugs that better target cancer cells more specifically may cause fewer side effects.

Your doctor and nurse will explain what you can do at home to prevent or treat side effects, such as:

  • Being careful with pets and other animals to avoid catching infections from them
  • Eating enough calories and protein to keep your weight up
  • Preventing bleeding, and what to do if bleeding occurs
  • Practicing safe eating and drinking habits, including being careful when eating out, knowing how to cook and store foods safely, and making sure your water is safe
  • Washing your hands often with soap and water

You will need to have follow-up visits with your doctor and nurse during and after chemotherapy. Blood tests and imaging tests, such as x-rays, MRI, CT, or PET scans, will be done to:

  • Monitor how well the chemotherapy is working
  • Watch for damage to the heart, lungs, kidneys, blood, and other parts of the body


Perry MC. Approach to the patient with cancer. In: Goldman L, Schafer AI, eds. Cecil Medicine. 24th ed. Philadelphia, Pa: Saunders Elsevier; 2011:chap 182.

Review date:
May 6, 2012
Reviewed by:
David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine; and Yi-Bin Chen, MD, Leukemia/Bone Marrow Transplant Program, Massachusetts General Hospital. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M. Health Solutions, Ebix, Inc.
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