Pregabalin is a newer-generation drug in the same class as
gabapentin. Limited information exists on its use in dogs as a
treatment for epilepsy. Based on pharmacokinetic data in normal
dogs, a dose of 2 to 4 mg/kg orally every eight hours has been
recommended and was administered to six dogs with idiopathic
epilepsy refractory to treatment with phenobarbital, potassium
bromide, or both drugs.11 One dog was considered a drug failure,
and four of the five remaining dogs had a mean seizure reduction
of 59.3%. Five dogs exhibited side effects (sedation and ataxia)
attributed to pregabalin. Zonisamide is a sulfonamide-derived
antiepileptic drug introduced in the United States in 2000. Its
half-life in dogs is 15 to 20 hours, which is relatively long
when compared with the other new antiepileptic drugs, and it
requires only twice-daily administration. Most of the drug is
excreted unchanged by the kidneys, although some hepatic
metabolism occurs. The dosage in dogs is 5 to 10 mg/kg given
orally every 12 hours. The