Seizures in Dogs and Cats

Seizures in Dogs and Cats

Jeremy Shomper MEd, DVM, DACVIM (neurology/neurosurgery)

MVMA Convention 2022

A seizure is the motor manifestation of uncontrolled cortical activity. Seizures are one of the most common neurologic problems in small animals. Seizures consist of multiple phases; the prodrome, aura, ictus, and postictal period. Other disorders such as vestibular events, dyskinesias, and syncope are often mislabeled as seizures, at least according to clients. Characteristics of seizures include duration (<2 to 3 minutes), stereotypical motor movements, autonomic dysfunction, altered level of consciousness, and an appreciable post-ictal phase. Notably, not all seizures have all of these characteristics. Since seizures represent cerebral dysfunction, a seizure localizes the problem to the forebrain. There are many types of seizure disorders, though we commonly encounter idiopathic epilepsy, neuroinflammatory diseases, and neoplasia.

There are multiple options to treat seizures in our patients including traditional therapies (phenobarbital, potassium bromide, benzodiazepines) and many newer therapies as well (levetiracetam, zonisamide, gabapentin, pregabalin, topiramate). Anti-epileptic drugs should be prescribed when an animal has had >1 seizure in a 6 month period, an episode of status epilepticus, head trauma within 1 month of seizure onset, or when a structural cause for seizure activity is diagnosed/suspected. Choosing an anti-epileptic depends on many factors including client compliance, cost, monitoring needs, and comorbidities.

Cats develop seizures less commonly than dogs and are also less frequently diagnosed with idiopathic epilepsy. Most anti-epileptic drugs are safe to use in cats though potassium bromide should be avoided. Cats tend to be dosed at a lesser level than dogs (phenobarbital) and there are currently ongoing studies regarding the use of levetiracetam in cats.

Cluster seizure treatment is very variable. In order to help alleviate the cost of repeated hospitalizations cluster prevention protocols are commonly utilized. This most commonly relies on pulse dosing either a maintenance medication or a benzodiazepine.

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