Potassium Bromide Is Now Fully FDA-Approved for Dog Epilepsy: What Changes for Owners

KBroVet, a potassium bromide chewable tablet, received full FDA approval to control seizures in dogs with idiopathic epilepsy, announced on January 21, 2026. Bromide has been used in dogs for a long time, so the medicine itself isn’t new. What’s new is that owners and vets now have an FDA-approved, quality-controlled product with an approved label, and that matters for a drug whose dose has to be adjusted to each dog and watched for toxicity.

How it got here

Idiopathic epilepsy, recurring seizures with no other cause found, affects about 5% of dogs, according to the FDA. In 2021, KBroVet (from Pegasus Laboratories) became the first drug conditionally approved under the FDA’s expanded authority, which it qualified for because no approved, marketed U.S. drug for canine idiopathic epilepsy existed. After four annual renewals, its maker met the standard for full approval.

It’s part of a broader shift. In September 2023, the FDA conditionally approved a phenobarbital tablet for dogs, Fidoquel-CA1, noting that “unapproved phenobarbital tablets from the human drug marketplace have historically been used in veterinary medicine.” And in December 2025, a heart drug, Vetmedin, became the first product on the expanded conditional path to reach full approval for a new use; KBroVet followed a month later.

How good is the evidence?

Honestly, weaker than for most new drugs. The FDA’s summary rests on two retrospective reviews of past cases and a review of the published research. “Neither of the retrospective studies included a control group,” the summary notes, so the results were compared with the roughly 29% response rate seen with placebo in canine epilepsy trials.

• First study: 18 of 27 dogs met the definition of success: at least a 50% drop in both seizure counts and seizure days, without seizures getting more severe.
• Second study: 40 of 46 dogs had at least a 50% drop in seizure frequency.

Both used potassium bromide on its own. Those are encouraging numbers, from a weaker kind of study than a randomized trial.

Side effects and warning signs

The most common side effects are increased appetite and thirst, weight gain, vomiting, wobbliness (ataxia) and sleepiness. The most consistent problem in the research was reversible neurologic signs, linked to high bromide levels or to combining it with other seizure drugs.

The FDA keeps it prescription-only to help avoid bromide intoxication, because dosing it takes a veterinarian’s expertise. Know the signs:

• Depression or behavior changes
• Incoordination
• Weak hind legs
• Dilated pupils
• Stupor or, in severe cases, coma

If you see any of these, call your vet.

Dosing and diet

The daily dose is adjusted to each dog; the label says it “should be adjusted based on monitoring of clinical response of the individual patient.” It can be given with or without food. But the FDA advises owners to avoid abrupt diet changes in dogs on bromide, so ask your vet before switching foods.

What it means for you

If your dog already takes bromide, ask your vet whether the approved product fits. If your dog has seizures, the most useful thing you can bring to every visit is a clear record. The free seizure log records the date, length, possible triggers and recovery of each seizure, and covers what to do during one, and a medication log keeps doses straight when they change.