A cure for what ails them? Questions remain about CBD therapy for dogs and cats

One late afternoon a couple of years ago, Karen came home to the troubling sight of her dog, Brumus, barely able to get up, dragging his back leg and suffering much pain. Bone cancer turned out to be the cause.

The veterinarian prescribed pain relievers, but it didn’t take long to see that they clearly were not enough. Then it occurred to Karen that CBD (cannabidiol – derived from cannabis) – based products helped ease pain in people, so maybe they could help her dog.

She bought hemp-based oils at her local natural foods store, and started to mix drops of it into Brumus’s food. Several tries later, Karen had found a product and dosage that worked well.

Then Brumus, during the final weeks of his life, was able to go out and play in the snow. He brightened up to his old, frolicking self, and Karen felt the CBD therapy gave Brumus more than an extra month with them.

Stories similar to this appear in the current issue of “All Animals,” published by the Humane Society of the United States. Right here on the North Fork, we hear of such bittersweet tales of dogs and cats, who got no relief from chronic arthritis pain with anti-inflammatory meds, but who walked around more comfortably after only a few days of starting CBD.

Is it, however, that simple? Do all animals respond well – sometimes dramatically well – to CBD? The questions go much further.

Is CBD therapy really good for pets? What do we know about CBD treatment for small animals, and what do we need to know? How well have we studied the adverse effects of CBD on dogs and cats? Can we trust the claims on the CBD product labels? Where is the FDA on CBD therapy for pets? How confident are veterinarians with recommending CBD, and how confident should we be in those recommendations?

Throughout New York State and nationwide, the use of CBD supplements is a hot and complicated topic in veterinary medicine. According to some professionals quoted at the website of the Veterinary Cannabis Society, formed to guide the profession with CBD studies and advice, CBD research is still in its infancy.

It is generally known to help dogs and cats with anxiety, epilepsy, osteoarthritis and pain control. This is based, however, almost entirely on anecdotal evidence — the personal experience of various individual cases. It has been a sort of trial-and-error approach that shows CBD’s value to pets for noise aversion, separation anxiety and other behavioral issues.

Veterinary neurologist and researcher Dr. Stephanie McGrath is one of the few known specialists and who has the added gift of saying it plainly: “CBD has its place for cats as well as dogs,” she says, “but we’re far from proving it.”

She goes on to explain that the longest time a dog has been on CBD in a controlled study is 12 weeks. Yet from that study, a still unanswered yet basic question is how does CBD work physiologically in dogs and cats.

Some issues may seem a bit technical, but worth considering: it’s known that CBD acts on different “ion channels” in the brain and nervous systems. Does this mean it actually alters neurotransmissions? And with CBD therapy, veterinarians have seen “elevations in liver enzymes,” but it is not known whether that means it is being metabolized by the liver, or that it is harming the liver. Negative reactions with other meds are not seen, but continue to be scientifically unclear and largely unstudied.

The U.S. Food and Drug Administration, for its part, actually discourages the use of CBD in these species, owing to scarce data on appropriate dosing, and as yet no real science on long-term effects on “serum chemistry,” and “pharmacokinetics.”

This reflects this agency’s overall reluctance about CBD therapy in general. Note that the FDA has approved only one human CBD drug, Epidiolex, for a rare form of epilepsy in people.

The legal side of the issue is unclear as well. The lack of FDA approval creates an interesting conflict of law. Fact: if a product has not been approved by the FDA, and is marketed as a therapeutic product, it is not being marketed legally. On the other hand, New York State law has only recently allowed veterinarians to discuss and recommend CBD therapy with pet owners. In many other states, vets still must avoid discussing it at all.

The limited research described in both the Veterinary Cannabis Society and the Humane Society of the US has shown some adverse effects of CBD therapy with cats: pacing, head-shaking, gagging, licking, drooling, foaming and vomiting. With both cats and dogs, there have been cases of a drop in blood urea nitrogen and triglycerides.

Yet the anecdotal evidence, the story after story of the beneficial experience of CBD therapy, particularly with pain management, as with Brumus above, is extensive. But how long will it take science to catch up, as our beloved pets have such short lives as it is?

A central point from all of this: at least thus far, the limited studies and few available experts tell us that hemp-based, CBD appears safe in healthy dogs and cats, with some adverse effects seen in both species.

Then there is the question of quality assurance in CBD products, sold currently as over-the-counter supplements. On a CBD products industry website, we are advised of a 2021 study by Leafreport.com, that found that more than half of CBD products on the market were inaccurately labeled; most of those contained more CBD than claimed.

And CBD products intended for human consumption often have ingredients, such as xylitol, that are toxic for pets. Experts seem unanimous in recommending against edibles, such as cookies or gummies, for use in animals. The need for this kind of background information underlies the reason that the Veterinary Cannabis Society was formed – to educate vets and improve industry standards.

What is a concerned pet owner to do with CBD product label concerns? Dr. McGrath recommends looking for companies that are readily able to provide “certificates of analysis,” what she describes as a “piece of paper that matches their CBD product to a clear and current description of the ingredients in that product.” She emphasizes that this whole product profile should be easy for the pet owner to understand. “Beyond that, we don’t know what’s in these products.”

In other words, we have to rely on what the CBD products industry tells us. As the profession that safeguards the world of pets, veterinarians have to be ever so careful. We don’t want another devastating scenario as with antibiotics or opioids for people, with the painfully slow if not horrifying catch-up by doctors, patients and regulators.

A final, compelling concern with CBD therapy, in particular for cases of behavior modification, is whether we are unwittingly altering our pet’s unique and cherished “personality,” in a way we don’t clearly understand.

Let’s close with reference to an informative resource, a free (until March 1st) 2018 HSVMA webinar, “Medical Cannabis in Small Animal Medicine.” CBD therapy can work for dogs and cats, but we owe it to them to get professional advice first.