Many pet owners notice changes in their dog's personality or behavior after an epilepsy diagnosis — and assume it is the medication, or their own stress, or something they did. The research tells a more complex and, in some ways, more validating story. Epilepsy itself — independent of medication — is associated with measurable behavioral and cognitive changes in dogs. You are not imagining it.

What the research has found

A study by Watson and colleagues published in Veterinary Record (2019) specifically examined behavioral changes in dogs with idiopathic epilepsy. It found that dogs with epilepsy showed significantly higher levels of fear, anxiety, and hyperactivity compared to neurologically normal dogs. These changes were present between seizures — not just during or after them — suggesting they reflect underlying neurological changes rather than simply a response to seizures.

Research published in The Veterinary Journal in 2024 by Peek and colleagues drew direct parallels between cognitive and behavioral comorbidities in human and canine epilepsy. The study established that epilepsy in dogs is "more than a simple seizure disorder" — it affects cognition, behavior, and emotional processing in ways that require holistic management, not just seizure control.

Medication effects versus disease effects

Some behavioral changes may be related to anti-seizure medication rather than epilepsy itself. Phenobarbital, for example, can cause sedation — particularly in the first few weeks of treatment — as well as increased appetite and thirst. Levetiracetam has been associated with behavioral side effects including agitation in some patients. Some behavioral changes may relate to seizure activity itself, medication effects, stress, or a combination of factors. Distinguishing between these requires working closely with your vet and keeping careful records.