Abstract
This article is intended to provide the veterinary community with a concise, understandable, and clinically relevant review of cannabis medicine in companion animals. Included are descriptions of the structure and function of the endocannabinoid system (ECS), outlines of the pharmacologic effects of biologically active compounds produced by the cannabis plant (phytocannabinoids, terpenoids, flavonoids), potential clinical uses and toxicities, relevant legal updates, and an overview of the most relevant veterinary research.
The ECS is a complex neuromodulatory signaling system that regulates multiple systems throughout the body and is often up-regulated or down-regulated in times of disease. Many cannabis-derived molecules have been shown to have multiple therapeutic benefits, including anti-inflammatory, analgesic, antineoplastic, anxiolytic, and anticonvulsant properties, through a variety of mechanisms. Although some of the naturally occurring compounds produced by the cannabis plant work in concert with the ECS, others have a unique pharmacology that produces important physiologic effects via ECS-independent mechanisms. Cannabis science is still in its infancy, and the research up to this point has centered around cannabidiol (CBD) or delta-9-tetrahydrocannabinol (THC). It is essential for veterinary practitioners to understand that the cannabis plant does not consist of a single therapeutic agent but rather a heterogeneous blend of a multitude of compounds.