Just in time for the Fourth, a new drug for noise aversion

We're getting close to many pet owners' least favorite time of the year:  fireworks and thunderstorm season. Around the Fourth of July and Labor Day, and during inclement weather with violent thunderstorms, we veterinarians know to expect an exponential increase in phone calls about noise anxiety1.    

Last year, I wrote a post on this subject in which I discussed methods of masking the noise and soothing your dog. I provided some techniques to desensitize your buddy to noise and use counter-conditioning to distract him.

I also mentioned drugs, something pet owners with seriously noise-averse dogs are usually willing to try. But many of our canine friends suffer without the benefit of anti-anxiety drugs because their people don’t like the side effects. When their pooch can hardly get up from the floor, staggers around the house as if he’s tipsy, or sleeps for an uncharacteristically long time, guilt ensues: Yikes, I’ve intoxicated my dog! In fact, excess sedation often merely calls for a dose adjustment, but pet owners usually don’t give the drug a second chance. 

What if there were a drug that calmed the jitters without causing drowsiness?

I seldom promote a new drug that I have little experience using, but the recent launch of Sileo (from Zoetis) is worth a mention. Norepinephrine is a chemical in the brain that is involved with the development of fear and anxiety. Sileo (dexmedetomidine) is highly selective in blocking the release of norepinephrine, thus mitigating dogs’ (specifically noise-induced) angst.

It’s actually not a new drug; we’ve been using the injectable form of dexmedetomidine for years as a sedative, and it has a good history of safety. What makes Sileo unique is the new delivery system: Applied to the gums, the drug calms without sedating ─ a real boon.  

Sileo is an oral gel dispensed in an easy-to-use multiple-dose syringe. (Don’t worry; there is no needle!) Because it’s efficiently absorbed through our skin, gloves should be worn while administering Sileo. Dosing is easy: The syringe is placed between the dog’s gums and cheek, and the plunger is pressed to dispense the product. It works by absorption via the mucous membrane in your dog’s mouth and shouldn’t be swallowed, which renders it ineffective. Therefore, neither food nor water should be offered for 15 minutes after treatment.

If you anticipate an anxiety-producing noise event, apply the Sileo 30 to 60 minutes beforehand. When an unexpected event occurs, just give the drug as soon as possible. It could take up to an hour to be effective, but that’s true of all the drugs used for this purpose (and some take even longer). You can administer up to five doses in one day, as long as the doses are at least two hours apart.

Sileo isn’t 100% effective in all dogs, but in clinical trials, 75% got good to excellent results. As with all drugs, there are contraindications. Sileo shouldn’t be used in dogs with severe liver, kidney, heart, or lung disease, or if a dog is seriously ill or pregnant. Some dogs may be sensitive to it and will exhibit sedation, a drop in body temperature, and a slowing heart rate. I recommend that dog owners be home to observe their pet’s response the first time they give Sileo.

The cost of Sileo depends on the size of your dog, and ranges from $2.50/dose for a toy dog (4.5 lbs. – 12 lbs.) up to $25/dose for a giant breed (196 lbs. – 220 lbs.). Treating dogs in the weight range we see the most (12 lbs. – 86 lbs.) will cost between $5 and $12.50/dose.

I’m not convinced that dogs with frequent noise-induced fear should be given this drug. I see patients that are afraid of just about every noise, and for them, there are better options, such as behavior modification and an SSRI (Prozac). But for the pooch with an isolated phobia (just fireworks, for example), time and experience will see whether this new drug can mean a more laid-back Fourth for Fido. 

^1. Here are some signs that your dog is afraid of loud noises: Pacing, panting, escape behavior, hiding, cowering, sticking to you like glue, loss of appetite, salivation, inappropriate urination or defecation, whining or barking, yawning, and excessive vigilance.