The gut-brain axis: effect of antibiotics on canine drug-resistant idiopathic epilepsy

Approximately thirty percent of the dogs with idiopathic epilepsy develop multidrug resistance. Therefore, the search for new non-drug treatment alternatives is important. There is a growing interest in the gut-brain axis and its role in the pathogenesis of epilepsy. The gut microbiota can influence brain function by different neural, endocrine, immune and metabolic pathways, but this process is not yet fully understood. In this study, five client-owned dogs with drug-resistant, idiopathic epilepsy received amoxicillin-clavulanic acid as add-on orally (mean duration 32 days (range 21-64 days)). The mean isolated epileptic seizure frequency of these five dogs was 3.3/ week (range 2.5-6.5) with a mean cluster seizure frequency of 0.9/week (range 0.4-1.5). During the amoxicillin-clavulanic acid treatment, three dogs showed complete seizure freedom, one dog showed an 80% decrease of both isolated epileptic seizure and cluster seizure frequency, and one dog showed an increase in isolated epileptic seizure and cluster seizure frequency of 54% and 38%, respectively. In the two-month follow-up period after cessation of the antibiotic administration, the mean isolated epileptic seizure and cluster seizure frequency increased again to 1.5 seizures/week (range 0.9-2.8) and 0.4 clusters/week (range 0.4-0.6), respectively. The preliminary results in this study highlight the need for future research into the role of the canine gut-brain axis in idiopathic epilepsy.