Cyclophosphamide

Brand names

• Cytoxan
• Neosar
• Procytox

Usage

To treat a number of cancers, including malignant lymphoma, multiple myeloma, sarcoma, retinoblastoma, leukemia, breast cancer, and ovarian cancer.

How it works

Cyclophosphamide kills cancer cells by interfering with the synthesis of their genetic material, which prevents malignant cells from multiplying.

Side effects

Serious

Shortness of breath, chest tightness, chest or abdominal pain, persistent cough or hoarseness, fever and chills, pain in the lower back or sides, painful or difficult urination, tiny bright red dots on the skin, unusual bleeding or bruising, breathing difficulty, blood in the urine or stool. Seek medical help immediately should any of these occur.

Common

Nausea and vomiting, loss of appetite and weight, temporary hair loss, increased susceptibility to infections, loss of hearing or ringing in the ears, sterility in men (usually temporary), unusual fatigue, increased pigmentation in skin and fingernails, dizziness, confusion.

Less common

Diarrhea, stomach upset, flushing, skin rash, itching, or hives, rapid heartbeat, swelling in the feet or lower legs.

Possible interactions

Other medicaments:

Cyclophosphamide taken concurrently with:

• allopurinol (Zyloprim) may increase the extent of bone marrow depression.
• amphotericin (Abelcet and others) may increase risk of kidney toxicity.
• chloramphenicol can decrease cyclophosphamide effectiveness.
• ciprofloxacin (Cipro) can result in lowered ciprofloxacin levels and the need for a larger than usual dose.
• digoxin may decrease digoxin absorption and impair digoxin's effectiveness.
• flu (influenza) vaccine, and perhaps other vaccines, may decrease the vaccine's ability to confer immunity.
• hydrochlorothiazide and other thiazide diuretics may worsen the lowering of white blood cells (myelosuppression) caused by cyclophosphamide.
• indomethacin (Indocin) can cause fluid retention.
• live-virus vaccines should be avoided.
• ondansetron (Zofran) may blunt benefits of cyclophosphamide.
• pentostatin may cause fatal heart damage.
• ritonavir (Norvir) may lead to cyclophosphamide toxicity.
• succinylcholine can result in succinylcholine toxicity.
• tamoxifen (Nolvadex) can increase blood clot risk.
• traztuzumab (Herceptin) may increase the risk of heart problems (congestive heart failure or ventricular dysfunction).

Herbal medicines or minerals:

Echinacea: some patients use Echinacea to attempt to boost their immune systems. Unfortunately, use of Echinacea is not recommended in people with damaged immune systems. This herb may also actually weaken any immune system if it is used too often or for too long a time.

Occurrence of unrelated illness:

Any signs of infection-fever, chills, sore throat, cough or flu-like symptoms-must be promptly reported. This medicament may have to be stopped until the infection is controlled. Consult your physician.