Cyclophosphamide for rheumatoid arthritis


Generic Name Brand Name
cyclophosphamide Cytoxan, Neosar

How It Works

Cyclophosphamide is an immunosuppressive medicine, which means that it decreases the effects of your body's immune system. By interrupting the immune process, cyclophosphamide reduces inflammation and slows joint damage caused by rheumatoid arthritis. Cyclophosphamide is a disease-modifying antirheumatic drug (DMARD), which means it controls the progression of the disease. DMARDs are also called slow-acting antirheumatic drugs (SAARDs).

Why It Is Used

Cyclophosphamide is used for severe rheumatoid arthritis that has not responded to other treatments, especially when there are also complications such as inflammation of blood vessels (vasculitis).

Cyclophosphamide is often used as chemotherapy in treatments for certain cancers, including non-Hodgkin's lymphoma and breast cancer. It is also used to suppress the immune system before a bone marrow transplant or after an organ transplant.

How Well It Works

Cyclophosphamide has been found to be effective in treating serious complications of rheumatoid arthritis such as vasculitis. Because of its serious side effects, cyclophosphamide is most often reserved for use in people with severe rheumatoid arthritis that has not responded to other treatments.1

Side Effects

Side effects of cyclophosphamide are common and can include:

  • Nausea and vomiting.
  • Allergic reactions.
  • Hair loss (alopecia).
  • Cessation of menstruation (amenorrhea) or early menopause.
  • Decreased sperm count (azoospermia).
  • Darkening of skin (hyperpigmentation).

Severe reactions can include:

  • Decreased bone marrow function and serious blood problems.
  • Bladder problems such as blood in the urine.

Because cyclophosphamide decreases the activity of your body's natural immune system, fever and chills are considered serious side effects that should be reported to your health professional immediately.

Cyclophosphamide increases the risk of infections such as herpes zoster (shingles). Prolonged use of cyclophosphamide is associated with an increased risk of some cancers, including bladder cancer.

If you take cyclophosphamide, you may have a slightly greater chance of getting cancer in your lifetime. This risk is small. But your doctor may check for cancer more often than if you did not take cyclophosphamide.

See Drug Reference for a full list of side effects. (Drug Reference is not available in all systems.)

What To Think About

Cyclophosphamide should not be used by women who are pregnant or trying to become pregnant. If you are a woman of childbearing age and are going to take cyclophosphamide, use some form of reliable birth control.

If you are taking cyclophosphamide, it is very important to drink plenty of fluids (around 3 quarts) each day to avoid bladder irritations.

Your doctor will schedule you for regular blood counts during treatment with cyclophosphamide.

Complete the new medication information form (PDF)(What is a PDF document?) to help you understand this medication.



  1. Lipsky PE (2008). Rheumatoid arthritis. In AS Fauci et al., eds., Harrison's Principles of Internal Medicine, 17th ed., vol. 2, pp. 2083–2092. New York: McGraw-Hill.

Last Updated: August 18, 2008

Author: Shannon Erstad, MBA/MPH

Medical Review: Anne C. Poinier, MD - Internal Medicine & Stanford M. Shoor, MD - Rheumatology

related physicians

related services

Bon Secours International| Sisters of Bon Secours USA| Bon Secours Health System

This information does not replace the advice of a doctor. Healthwise disclaims any warranty or liability for your use of this information. Your use of this information means that you agree to the Terms of Use. Privacy Policy. How this information was developed to help you make better health decisions.

© 1995-2010 Healthwise, Incorporated. Healthwise, Healthwise for every health decision, and the Healthwise logo are trademarks of Healthwise, Incorporated.