Cyclophosphamide (Cytoxan®) Side Effects and Precautions

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What Is Cyclophosphamide?

In lower doses, cyclophosphamide (Cytoxan®) is an immunosuppressant drug used to reduce the natural immunity of patients who receive organ transplants such as liver transplants. In higher doses, cyclophosphamide is used to treat certain cancers.

Cyclophosphamide medication uses

Cyclophosphamide prevents the white blood cells from causing rejection.

Cyclophosphamide Dosage

Cyclophosphamide is taken by mouth or is given by injection. The oral medication is available in 25-mg and 50-mg tablets.

How to Properly Take Cyclophosphamide

Cyclophosphamide can be taken with or without food. If your child has an upset stomach while on this medication, try giving the doses along with food. Some patients find that taking cyclophosphamide with a full glass of water while their stomachs are empty helps relieve vomiting. Changing the frequency of eating – such as eating several small meals rather than a few big meals – or limiting activity may also lessen vomiting.

Also, while your child is on cyclophosphamide and for 24 hours afterwards, he or she should drink extra fluids and urinate regularly. This helps your child’s kidneys remove the drug from his or her body and avoids some of the side effects.

Missed doses

If your child misses a dose, inform your doctor or clinical coordinator. Do not double the dose to catch up. For optimal benefits, your child must take each dose of medication as scheduled and directed.

Cyclophosphamide Side Effects

Aside from nausea and vomiting, it is possible your child will experience diarrhea or generalized stomach pain. You may notice that he or she has less of an appetite than usual, or sweats more than usual. Some people taking this medication say they feel unusually tired or weak, or get headaches. Hair loss may also occur, but it is temporary.

Rarely, cyclophosphamide side effects in children may include:

  • Bruising or bleeding
  • Painful urination
  • Lower back or abdominal pain
  • Persistent cough
  • Rash
  • Hives
  • Itching
  • Difficulty breathing
  • Redness
  • Swollen lips
  • Fever
  • Chills
  • Sore throat
  • Blood in urine
  • Dizziness
  • Darkening of the skin or fingernails

If your child has trouble with any of these side effects, inform your transplant doctor.

Cyclophosphamide Drug Interactions

Tell your doctor or pharmacist about any prescription or over-the-counter medication your child is taking, so you can be warned of interactions and prevent them.

Precautions for Pediatric Patients

Cyclophosphamide may reduce the number of blood cells in your child’s blood. Since blood cells are needed for clotting, your child may bleed more easily and heal more slowly. To prevent bleeding, avoid situations (as much as possible) where bruising or injury might occur.

Learn more about other Liver Transplant Drugs.