The Role of Compounding Pharmacies in Cancer Care for Pets

Barbara Cohen, March 9, 2018

Animal Cancer Foundation - The Role of Compounding Pharmacies in Cancer Care for Pets

My veterinary oncologist wrote a compounding pharmacy prescription for my pet.  Why?

In many circumstances, cancer therapeutics are not specifically manufactured for our pets.  This is especially true, currently, for targeted therapeutics that are available for use in people.  For example, the targeted therapeutic Dasitinib, sold by Bristol Myers Squibb under the brand name Sprycel, is not available for veterinary oncology patients.  In a case like this, the specialist will write a prescription to have the drug compounded by a licensed compounding pharmacy, which will mix the drug to create a medication specific to the individual needs of your pet.  

Specialists also use compounding pharmacies to alter the size of the dose specifically for your pet.  Many drugs are prescribed by weight, or what is known in veterinary medicine as milogram by kilogram, and which may not be available in a dose calibrated for a small animal.  The compounding pharmacist creates the appropriate does in this case, working side-by-side with the veterinary professional.

According to Brian Morgan, Director of BestPetRX, a compounding pharmacy located in New York City, "Our great opportunity is to work as a think-tank alongside the veterinary professional to make it easier for the veterinary team, the pet parent, and the pet, especially the pet with a condition like cancer, to have medication that is effective, appropriate, and least difficult to give to the pet."

Mirtazapine (sold by Merck under the brand name Remeron), a commonly used human anti-depressant that has been shown to be an effective appetite stimulant for and anti-nausea medication for pets, is only available in pill form.  If you've ever tried to give medication to your cat, then you understand how difficult pilling your cat can be, especially if "Tigger" is already feeling poorly and is experiencing loss of appetite commonly associated with cancer and cancer treatment.

Compounding pharmacists are able to alter the delivery of medications into formulations, not normally available, for safe use in your pet when a licensed veterinarian has decided that this formulation is necessary.  For Mirtazapine, compounding pharmacists have been able to create transdermal creams or gels dispensed from a syringe to the pet's inner ear.  The unique delivery system for this drug, which is currently being studied by Dr. Jessica Quimby at Colorado State University College of Veterinary Medicine and Biomedical Science for effectiveness in cats with kidney disease, is much easier to administer than to an ill pet and uses the properties of the highly vascular inner ear to ensure that the medication effectively reaches the target.  

Another way compounding pharmacists support the pet with cancer is by flavoring gastrointestinal protectants or anti-diarrheal medications to induce pets to comply with treatment, similar to the way in which human pharmacies flavor medications for children.  According to Morgan, "cats are particulary fond of vanilla butternut flavor, although every pet is an individual and the compounding pharmacist uses information from the pet parent and the veterinary specialist to create flavors to suit the pet."