Evaluation of the Most Frequently Prescribed Extemporaneously Compounded Veterinary Medications at a Large Independent Community Pharmacy

Abstract

Extemporaneous drug formulation is essential to provide optimal pharmaceutical care to veterinary patients. The need for this is exacerbated by the fact that commercially produced veterinary-specific products, without a human indication, require specialty veterinary manufacturing facilities and a new animal drug application process to gain marketing approval. This study examined the prescription patterns of extemporaneously compounded veterinary preparations in the compounding department at a large independent community pharmacy. Data was obtained from a total of 1348 prescriptions requiring extemporaneous compounding over the course of a two-year period (2014-2015). A database was constructed and each compounded prescription was allocated to a therapeutic category based on the American Hospital Formulary Service Drug Information. Data analysis showed that the most commonly prescribed preparations belonged to the central nervous system (39%), anti-infective agents (21%), and hormones (12%) therapeutic categories. Overall, suspensions were the most dispensed (47%), extemporaneously compounded dosage forms followed by solutions (28%), and capsules (10%). The majority (88%) of compounded preparations were administered by the oral route. The top three drugs that are compounded for veterinary medicine were (1) potassium bromide oral solution for canine epilepsy, (2) methimazole solution used to treat hyperthyroidism in cats, and (3) metronidazole suspension, an antibiotic for the treatment of diarrhea and other infections in dogs and cats. Remarkably, our findings are in good agreement with previously published survey data on the top drugs that are compounded for veterinary medicine. In the era of personalized medicine, veterinary extemporaneous compounding for specialized needs will continue to play an important role providing optimum therapy for veterinary patients.