Pot Matters: Cannabis and Veterinary Medicine

A recent article in the scientific journal Veterinarni Medicina is providing an overview of the potential use of cannabinoids in veterinary medicine. The article reviewed relevant research on the cannabinoid receptor system, findings from research projects testing cannabinoids on various animal species and current applications of cannabinoids in veterinary medicine.

The peer reviewed article explains that the increased attention to the medical use of cannabis in human medicine has prompted animal owners to investigate the use of cannabinoids in veterinary medicine as well.

Veterinarians have been reluctant to pursue this topic because “the use of cannabinoids/medical marijuana in animals could be associated with the risk that owners will make attempts to treat their animals using cannabis-based products, which can lead to intoxication.” As in the case of human medicine, scientific literature will play an important role in giving veterinarians a reliable knowledge base with which to guide their medical practice.

The authors report that the therapeutic potential of cannabinoids has been demonstrated “in the treatment of many disorders including pain, inflammation, cancer, asthma, glaucoma, spinal cord injury, epilepsy, hypertension, myocardial infarction, arrhythmia, rheumatoid arthritis, diabetes, multiple sclerosis, Parkinson’s disease, Alzheimer’s disease, depression or feeding-related disorders and many others.

As a preliminary stage in the process of investigating the medical use of cannabinoids in humans, there has been considerable research on their impact on animals, particularly with studies of mice, rats and guinea pigs regarding “disorders of the cardiovascular system, cancer treatment, pain treatment, disorders of the respiratory system or metabolic disorders.” Smaller numbers of papers have been published regarding pre-clinical testing on rabbits, ferrets, cats and dogs, and less regarding companion and larger animals.

Some of the research discussed in detail includes the use WIN 55212-2 (a cannabinoid receptor antagonist) to reduce intraocular pressure in animals with glaucoma and the use of “an endogenous fatty acid amide analogue of the endocannabinoid AEA—termed palmitoylethanolamide (PEA)— in tissue protection.” PEA has shown great promise in the treatment of skin disorders, particularly in dogs with skin allergies. Another promising area involves the use of cannabinoids to stimulate appetite in animals with cancer.

Addressing concerns over the psychotropic properties of cannabinoids, such as their effect on locomotion and addictive potential, the authors point out that “other drug classes with even stronger effects on the CNS [the Central Nervous System] and addictive properties have been used therapeutically in both humans and veterinary medicine for centuries (e.g. opioids) because their benefit outweighs the risks.”

Part of the paper’s argument for the use of cannabinoids in veterinary medicine is that cannabis-based products for humans are now available in Austria, Canada, the Czech Republic, Finland, Germany, Israel and Italy. Commercial pharmaceuticals for humans now include such products as Cesamet, Dronabinol, Sativex, Bedrocan, Bedrobinol, Bediol, Bedica and Bedrolite.

In veterinary medicine, a hemp-based supplement with non-psychoactive cannabidiol, Canna-Pet, is now on the market. Redonyl, a PEA product, is also now available to restore skin reactivity in animals as a veterinary medication.   

As an indication of increased interest in the use of cannabinoids to treat animal medical problems, researchers observed that there are a “number of internet forums concerned with this issue (e.g. dvm360 magazine, Cannabis Financial Network or Medical Daily).”  They also refer to a June 2013 article in the Journal of the American Veterinary Medical Association documenting “reported anecdotal evidence from pet owners describing beneficial effects of marijuana use in dogs, cats and horses and, moreover, also the opinions of professionals who believe in the potential usefulness of cannabis use in veterinary medicine.”

The push is on for veterinarians to join the debate over the use of medical cannabis to treat animal medical ailments, including advocacy in favor of clinical trials in such areas as using cannabinoids to treat cancer pain in animals.

The researchers argue that public interest in the medical use of cannabis for animals is growing, and without leadership and utilization of medical cannabis by the veterinary community, this will result in “attempts at treatment using cannabinoids without the necessary safety precautions.”  

Veterinarians need to take the prospective uses of medical cannabis seriously. This can help advance treatment and care for animal patients, and also decrease the risks to animals from non-professional treatment by owners.

(Photo Courtesy of Animal Health Associates)