Apoquel: The Dog Miracle Drug With A Dark Side

Reprinted with permission of Dr. Will Falconer, DVM

When you have a crazily itchy dog or cat, everybody suffers. Patients in this state often keep you up at night and drive you crazy during the day dealing with the mad itch.

Scratching, biting, losing hair, skin red and inflamed, these guys often stink, ooze sticky moisture from their skin, and many can’t get comfortable long enough to take a decent nap, let alone sleep the night through.

Talk about a pain for you and your loved ones! At the base of wildly itchy animals is the immune system, which is working overtime, but malfunctioning. “Dysregulated” is a term used in the scientific papers. (We have to insert a wink here because immune system dysregulation is entirely a man-made disease. More on that later.)

Interestingly, most look right past that important man-made point and seek to “fix” the itchy beast with powerful drugs. Enter the latest anti-inflammatory drug to make a splash in the veterinary market: Apoquel (oclacitinib).

And lest you think I’m recommending it, you’ll want to read on for the details about why an abundance of caution is recommended before you plunk down your hard-earned money and start your dog down a potentially dangerous path. Apoquel is not for puppies. Or cats or people. It’s Apoquel for dogs that we’re talking about.

Born from the loins of the world’s largest drugmaker, Pfizer, their former division Zoetis is now the “animal health” giant that brought this much-touted wonder drug to market in 2014. How big is Zoetis? $4.34 billion in revenue in 2012, before Apoquel had even hit the market.

So, it’s BIG.

Stops Itch FAST! The claims of Apoquel and even the actual results in itchy dogs are amazing. “Provides onset of relief within 4 hours. Effectively controls itch within 24 hours.”

Irresistible, right?

After you’ve lost sleep for weeks on end and tried everything offered you by Dr. WhiteCoat and Dr. Google without success, wouldn’t this sound like heaven in a pill?

Apoquel: How Does it Work?

Ah, now you’re asking a smart question. How Apoquel works is the key to why you need to be smart. In fact, you need to be smarter than the marketers, smarter than Zoetis, and smarter than Dr. WhiteCoat, who’d all be tickled to sell this to you.

It works! But why should we take Zoetis’ word for it. Given that they did safety and efficacy research for only 30 days, I’m not so sure. And then there’s this: can you say conflict of interest?

Pull up a little closer to the campfire for this part, because here’s where the story gets good. To know how the drug works, you should know first how The Itch works. Here’s what a board-certified veterinary dermatologist says causes The Itch:

• Flea allergy dermatitis
• Atopic dermatitis
• Food allergy dermatitis
• Contact dermatitis
• Sarcoptic mange
• Demodectic mange

I really, really wish I was making this up. This vet is merely listed itchy diseases, but nothing about their causes. While this explanation is seriously lacking in the “why?”, the part he does get right is this: itchy, allergic skin is the #1 reason pets go to vets. This  has been true for about 15 years now. Hard insurance data tell no lies.

Remember that wild and crazy immune system spoken of earlier? The one that’s off the rails, acting all whacky and dysregulated? That’s what Apoquel is acting on. It’s being called an “immune modulator” by the experts. That’s an enticing way of calling out its action. Sounds suspiciously benign.

Keep reading though, and you’ll see that it’s anything but. Here’s a brief description of how this “wonder drug” called Apoquel works.

If you like what you’re reading here by Dr. Falconer, be sure to sign up for a membership to hear Dr. Tenpenny’s interview and Deep Dive with Dr. Falconer on general animal health! Below is a short excerpt from that interview.

Immunology 101

First, an important understanding. While it might seem like we know a lot about the immune response, there are still large swaths of mystery we don’t yet comprehend. By its very nature, this is one complex system! If we didn’t have it, we’d have been lost as a species a very long time ago, right along with our pets and our livestock. That said, we know there are lots of messenger molecules involved.

And sweeping events called cascades, where the right trigger (a virus, say) causes a series of chemical messages and events that, when all is working well keeps you and your animals out of harm’s way.

“Yo. We Need to Talk”: One group of immune messengers are called cytokines. These small molecules are produced by a wide variety of cells, and they signal other cells to do something like come to the scene of infection, let loose their chemicals, take part in signaling others, dump antibodies, etc.

You’ve likely heard of some cytokines before: interferon, interleukins, tumor necrosis factors.

When inflammation is triggered, these chemical messengers call in the troops: “It’s time to heal!”

(More on inflammation in context here. It’s not the enemy, by the way.)

Enter Apoquel (oclacitinib). A couple of words hidden in those names. A whole class of inhibitory compounds man has invented have “inib” at their end. Short for inhibit. And “quel?” You get that one. Chill out this hot mess of inflammation! So, this drug seeks to stop a piece of the inflammatory chemical cascade by interfering with certain enzymes called kinases, or JAK in the literature, which stops some cytokines from doing their thing.

And it works! But like all things that “work,” we need to look a bit deeper if we want to raise truly vital animals. “Work” can mean cure but it more often means palliation. Palliation means, while the medicine is being given, the symptoms are relatively controlled. The animal is no better overall and once the drug stops, the symptoms return. In the meantime, the disease is slowly growing and getting less likely to be able to be cured.

Usually, there’s a price to pay in long term health when we interfere with Mother Nature, and this drug is no exception.

Apoquel and Long Term Safety? Not So Much.

My Texas colleague Dr. Ron Hines has done a brilliant job of cataloging feedback from animal owners actually using this drug. You, dear readers, have also contributed many, many of your own experiences in the comments on this article. When you read past the glowing reports of “Hallelujah! Peace at last!” you start to pick up a theme.

Those who’ve been using this drug for a while are seeing two common problems. Variations of these occur in most all drugs, in fact, not just this one: side effects, and no longer helping as much as it did at first. My original article has several testimonials like this one, a story of a Bishon who had eight months on the drug:

“The drug has given my dog (four years old) a quality of life I never thought was possible. He also receives an allergy serum injection every ten days. However, for the past several weeks his nose has been running constantly and as of late he has been gurgling rather than breathing. Two days ago, his nose was bleeding. I stopped the Apoquel immediately and will see the allergist this week. Most importantly, two days after I stopped the Apoquel, his nose dried up, no more running and no more blood. I cannot help but assume that the Apoquel was the cause of his misery.”