Tessie: The First FDA-Approved Drug for Both Noise Fear and Separation Anxiety

On May 6, 2026, the FDA approved Tessie (tasipimidine), the first drug approved in the U.S. to treat both noise aversion and separation anxiety in dogs. It’s a prescription liquid given about an hour before the trigger, it helped more dogs than a placebo did in its trials, and it often makes dogs drowsy. One catch for this season: its maker doesn’t expect it in U.S. clinics until mid-2027.

What it is and how it works

Tessie is an oral solution made by Orion Corporation of Finland; according to Orion, Zoetis holds the U.S. marketing rights. Tasipimidine is an alpha-2 agonist: in the FDA’s words, it works by “activating specific receptors in a dog’s brain to decrease heightened sympathetic nervous system” activity, the fight-or-flight response that drives panting, pacing and panic.

The FDA made it prescription-only on purpose, because, as its approval summary puts it, “professional expertise is required to properly diagnose noise aversion and separation anxiety.” So the first step is a vet visit, not a pharmacy.

The trial numbers

The FDA publishes a summary of the evidence behind every approval. Here is what Tessie’s shows.

Fireworks. In a randomized, double-blind trial of 160 pet dogs, the test day was New Year’s Eve (2016/2017, in Finland, Germany, Denmark and Portugal). Owners rated the effect “good” or “excellent” in 54% of dogs on Tessie and 35% on placebo. That gap is real (statistically significant), and the placebo number is worth noticing too: about a third of the untreated dogs also had a good night, so the drug’s added effect is moderate.

Separation anxiety. An eight-week, double-blinded trial of 224 dogs, scored by owners from video of the dog home alone, clearly favored Tessie. The clearest number: 60% of the control dogs needed rescue medication, against 17% of the Tessie dogs. The FDA summary doesn’t give a simple “percent improved” for this trial.

Both trials were done in Europe, and the outcomes were rated by owners, who didn’t know which treatment their dog got.

Side effects

The main one is sedation, which makes sense for a drug that calms the stress response.

Seen in the separation-anxiety trial	Tessie	Control
Slow to stand up, but walking normally	48%	8%
Vomiting	25%	10%
Lethargy	17%	4%
Slow to respond to their name	17%	1%
Diarrhea	12%	8%
Elevated liver enzymes	4%	2%

In the fireworks trial, within two hours of the first dose, 12% of treated dogs (against 5% on placebo) couldn’t walk normally or stand up. In laboratory safety studies, the sedation always wore off before the next day’s dose.

There’s an obvious tension here: a drug for being left alone that can leave a dog groggy. The label handles it directly: “Do not leave your dog alone if it is drowsy after dosing.” That’s why a supervised test dose comes first.

How it’s given

Following the FDA-approved label, your vet will typically:

• Have you give it by mouth about an hour before the expected noise or before you leave.
• Ask you to give it on an empty stomach: at least an hour after a meal (a small treat to help it go down is allowed).
• Cap it at three doses in 24 hours, at least three hours apart.
• Never give a dose to a dog that is still drowsy from an earlier dose.
• Start with a test dose while you’re home, watching for two hours; if your dog gets drowsy or wobbly, the vet may lower the dose.

The liquid can be absorbed through the eyes or mouth, and accidental exposure can cause sedation and blood-pressure changes in people, so an adult should give it, and you shouldn’t drive if you get some on you.

What it won’t do

It won’t replace the plan. The label says that “depending on the level of arousal, the signs of noise aversion may not be completely eliminated.” For fireworks, that still means a safe room, masking sound and low-volume practice in the quiet months; for separation anxiety, gradual practice with short absences. If you’re not sure which problem your dog has, the free noise fear test and separation anxiety test take two minutes and tell you what to bring to your vet. And for this New Year’s Eve, the fireworks prep checklist covers the night itself.

When you can get it

The FDA approved it in May 2026, but Orion expects it to be available in the U.S. by mid-2027 (the company’s own estimate). In the European Union it has been authorized since August 2021, on prescription, in 27 countries including Spain, with a slightly narrower wording: “short term alleviation of situational anxiety and fear” triggered by noise or the owner leaving.