1. Health
You can opt-out at any time. Please refer to our privacy policy for contact information.

Cytoxan (Cyclophosphamide): Chemotherapy for Breast Cancer Treatment


Updated June 19, 2014

Cytoxan powder

Cytoxan powder

Photo © Drugs A-Z

Definition of Cytoxan:

Cytoxan is a chemotherapy drug that is used in combination with other drugs to treat cancer. It is derived from mustard gas, and is an anti-tumor drug.

Use For Breast Cancer:

Cytoxan is often combined with two other drugs, Adriamycin and 5-Fluorouracil, in a chemotherapy infusion to treat breast cancer. This combination is called AC, FAC or CAF. Another chemotherapy combination being used for breast cancer is Taxotere and Cytoxan. There also is a very old but still commonly use mixture called CMF, which has Cytoxan, methotrexate and 5-flouracil.

Other Uses for Cytoxan:

It is used to treat breast and ovarian cancers, as well as lymphoma, leukemias, multiple myeloma, mycosis fungoides, neuroblastoma and retinoblastoma.

Also known as:

Cytoxan, Neosar, Clafen, cyclophosphamide

How Cytoxan Works:

Cytoxan works on cancer cells by damaging their RNA or DNA when they are in their resting phase (not dividing). Because Cytoxan causes breaks in the DNA of cancer cells, they can't keep dividing, and they die. This drug will also affect normal cells, but will have less affect on those cells, since they divide more slowly and are better able to fix DNA breaks than cancer cells. Some of your normal cells that will be affected include: blood, mouth tissue, digestive tract and hair follicles.

How Cytoxan is Given:

Cytoxan is often given in fluid form during an intravenous chemotherapy infusion. It can also be given in pill form, and it must be taken with large amounts of water, to prevent irritation, and possible damage to your kidneys and bladder.

Recommendations During Treatment:

  • Use reliable contraception
  • Drink lots of fluids, especially water, to flush your kidneys and bladder
  • Avoid alcohol and caffeine
  • Don’t take aspirin - take ibuprofen instead
  • Don’t get vaccinations

Risks of Using Cytoxan:

  • Allergic reaction
  • May harm fetus, if you become pregnant during treatment
  • Possible future infertility
  • Low blood counts, greater danger of infections

Possible Side Effects:

  • Neutropenia (low white blood cell count, greater risk of infection)
  • Low platelet count
  • Hair loss
  • Nausea
  • Vomiting
  • Diarrhea
  • Fatigue
  • Mucositis (irritated mucous membrane in your mouth)
  • Amenhorrea (monthly menstrual cycle stops)
  • Changes in nails (brittle or yellowed)

When to Call Your Doctor::

If you have any of these symptoms, call your doctor:
  • Fever of 100.5°F or higher
  • Painful or bloody urine
  • Black and sticky (tarry) stools, or bloody stools
  • Unusual bruises or bleeding
  • Persistent cough, pneumonia
  • Allergic symptoms: shortness of breath, swelling of feet or ankles, rash, swollen throat

U.S. Food and Drug Administration. FDA Oncology Tools Product Label. Details in Conventional Order for cyclophosphamide. Last updated: July 1, 2000.

National Cancer Institute. Drug Information – Cyclophosphamide. Last Updated: 11/06/2007.

American Cancer Society. Drug Guide. Cyclophosphamide. Last updated: 2004.

  1. About.com
  2. Health
  3. Breast Cancer
  4. Treatment Options
  5. Chemotherapy Drugs
  6. Cytoxan Chemotherapy for Breast Cancer Treatment

©2014 About.com. All rights reserved.

We comply with the HONcode standard
for trustworthy health
information: verify here.