(Cytoxan® is another name for this medication.)

Use: Cyclophosphamide is used to treat cancer and some diseases that are caused by an overactive immune system.

Side Effects: Cyclophosphamide can be toxic to the heart at higher doses (Report any irregular heart beats or rates to your veterinarian). Cyclophosphamide may cause stomach upset and can be given with food to reduce this side effect. Hair loss is common in those breeds of dogs that are continuously growing hair (e.g., Poodles and Old English Sheepdogs). Cyclophosphamide may cause bladder irritation. You should leave lots of clean water for your pet to drink and report any signs of blood in the urine or frequent urination to your veterinarian immediately. 

Precautions: Any waste from this animal (feces, urine, and saliva) should be cleaned up with gloves for at least 48 hours after the last treatment with cyclophosphamide. Waste should be disposed of in a sealed plastic bag because cyclophosphamide can cause immune suppression in humans, you should wear gloves and wash hands after giving this medication.

Directions: Dogs and cats usually get this drug orally 4 days out of 7 for 6-8 weeks in a cancer treatment program. You must take your pet back to the veterinarian frequently for very important blood work checkups. 

Remember: You should not split or crush these tablets unless directed by your. Cyclophosphamide should be protected from light and moisture and stored at room temperature.

If you miss a dose of this medication you should give it as soon as you remember it, but if it is within a few hours of the regularly scheduled dose, wait and give it at the regular time. Do not double a dose as this can be toxic to your pet.