Non-Pharmaceutical Pain Management in Companion Animals

B. Duncan X. Lascelles, BVSc, PhD, DACVS: Beyond the monoclonal antibodies, Sheilah, what other areas of pain management research do you think are underserved or are somewhat neglected? Where would you like to see research focused?

Sheilah Robertson, BVMS, PhD, DACVAA, DACAW: I think one of the areas that is talked about an awful lot is the use of cannabinoids, and that is an evolving discussion for both humans and animals. And within the United States, it varies between state to state. For humans, who has access to it—whether it’s legal, illegal, or all the issues around cannabinoids? But if you think about it, we developed opioids hundreds of years ago, because there is an endogenous opioid system in our bodies. So, now that we know that there’s a cannabinoid endogenous system, why is it there? There has to be a reason why it’s there.

I think the research around cannabinoids is very, very important, and that we should focus on it. The problem is, there are legal issues. It’s very, very difficult to do research because of how those drugs are scheduled. But we have to be very aware that animals and CBD (cannabidiol), and how it acts in a dog and a cat, is very, very different from how it acts in a human. And we’re not talking about THC (tetrahydrocannabinol), the negative connotations of the cannabinoids, but we have to completely understand and realize that owners are using these products.

We can’t legally prescribe them. We know very little about them, but the owners can buy them online without any problems. They can, in certain states, just go buy them. They’re using them, so I think we really need to think about some really good research and how we could effectively use cannabinoids. And I would say the data in humans are very, very encouraging for a lot of chronic diseases and effective states. But we really have very little data in dogs, cats, or any other species.

B. Duncan X. Lascelles, BVSc, PhD, DACVS: And moving beyond that, Mark, what other tools would you like in your toolbox? What areas do you think need to be addressed, from a primary practice point of view? What are the problems that you’re trying to manage day in, day out?

Mark Epstein, DVM, DABVP, CVPP: The blessing is that the toolbox is full. The curse is that the toolbox is full. We have a lot of things we can use. The data to support them all are what are really limited. So, I have a long list of things that I would like to know more about.

B. Duncan X. Lascelles, BVSc, PhD, DACVS: Where would you prioritize our greater understanding?

Mark Epstein, DVM, DABVP, CVPP: Wow. I think a simple place to go—some low-hanging fruit—would be to address some of the drugs and products that are already out there, already easy to get, legal, and not even regulated. We could speak of the contra protectants—the nutraceuticals. It’s a gazillion-dollar industry in humans and in veterinary medicine, and yet the data in humans are conflicting, at best. We have the models. We should be able to prove that it works or not. And so, those companies, in my view, should get on the stick.

The same can be said for some of the non-pharmacologic modalities, whether it’s therapeutic laser, pulsed electromagnetic field, or even acupuncture. And all of these things, since we have the models—they may be imperfect, but we have the model—should be explored and put under robust, well-designed studies that are big enough to power through that caregiver placebo effect. We can put a number on that: In dogs, it’s 25% or up to 50%; in cats, 90%.

Margaret Gruen, DVM, MVPH, PhD, DACVB: Higher.

Mark Epstein, DVM, DABVP, CVPP: Right. They have to be really well-designed studies, and big. I know that that takes money, but that’s what will convince me that we should be using those kinds of products more ubiquitously than we currently do. The more low-hanging fruit is that there is a whole bucket of medications that are used in humans for pain, and yet, if we’re lucky to have some pharmacokinetic data on them in dogs and cats—that’s about all we have got. In fact, as far as I know, there’s only 1 molecule that has been looked at as an adjunct in nonsteroidals for osteoarthritis in dogs. And that molecule, amantadine, Dr. Lascelles, was highlighted in your study. Other than that, we have nothing. There are none for cats. And yet, we have all these drugs that are available for humans, in that department.

And then, lastly, I would say that there’s a dimension that gets back to what Sheilah was talking about with quality of life. In humans with chronic pain, we know about controlling for other factor; controlling for age, even. People with chronic pain have cognitive changes. They have learning problems, memory problems, mental agility issues, and clinical depression. And these are things that I know may be hard to pick up, but I’d like to throw it back to Margaret, because I know that’s her wheelhouse. That’s a really exciting area for me, and I’d love to be able to deploy medications and interventions that can improve both.