articles for Veterinarians

Veterinary Compounding – A Few Basics

Compounding plays an important role in veterinary medicine, particularly when manufacturers leave us with a variety of therapeutic gaps. But to many veterinarians and staff members, compounding is understandably an afterthought. They are much too busy to play the role of pharmacist. But it is important to have a cursory knowledge of the medications prescribed. Not every drug can or should be compounded into different formulations, but for those that can, compounding may provide the most productive solution.

We’ve found that our veterinary colleagues appreciate a more consultative approach to helping them manage their patients pharmacologically. The current model of requesting a medication from a facility without collaboration feels disconnected and risky. Fortunately, more educational opportunities are emerging. Here are a few important compounding insights:

Oral Liquids:
Liquids are an excellent alternative to your clients trying to manage cutting tablets; a difficult task given the nature of some prescription drugs. Small doses can be easily achieved through compounding medications into lower concentrations. We often assist in formulating the medication into appropriate liquid administration volumes, usually 0.1-0.5 mL for most small animal patients. Species appropriate flavoring can be added to aid in patient compliance. Marshmallow flavoring is an excellent addition to suppress bitter tasting medications (tramadol, clindamycin, metronidazole). Beyond use dates (BUD) may vary between compounds depending on the suspending vehicle used. Be suspicious of any water-based product with a BUD longer than 90 days. Oil based vehicles can increase client compliance with a BUD of 6 months.

Capsules, Micro Tablets, Medicated Treats:
Compounded capsules allow for customized medication strengths when a suitable FDA approved dosage strength is unavailable (usually outside of a window of +/- 10%). As with oil-based suspensions, most capsules have a BUD of 6 months, improving client compliance through the ability to purchase more than one month’s supply at a time. For patients that have a hard time swallowing larger tablets, micro tablets may be a way to provide the dose needed in a smaller, more manageable size. Medicated treats offer an enticing medication option for patients that are hard to pill.

Transdermals:
Transdermal medications can aid in medication adherence for difficult to pill patients. Be aware that not all medications are appropriate to put into a transdermal formulation. Some medications can have unpredictable absorption, leading to therapeutic failure or even toxic drug levels. Other medications can be irritating or, in the case of corticosteroids, risk causing cartilage atrophy. It’s not recommended that you use a transdermal formulation that lacks evidence of safety or efficacy.

Otic Packs:
For complicated, persistent ear infections, otic packs may be an option. The ingredients can be tailored to the results of bacterial cultures. These products also improve client compliance and therapeutic outcomes by eliminating the need for daily ear drop application. Many clinicians are familiar with lanolin-based products but there has been a growing interest toward otic packs that utilize PLO gel (Pluronic Lecithin Organogel). This is a unique thermos-reversible base that eases administration, decreases the anecdotal concerns of causing deafness and has great absorption data.

Having a baseline knowledge of compounding essentials can create a rewarding collaboration between pharmacists and veterinarians. Compounding is a blend of art and science, that when used appropriately, can provide inventive solutions tailored to unique patient needs.