Abstract: Background: Approximately 30% of dogs with idiopathic epilepsy are refractory to treatment. Recent studies have suggested cannabidiol (CBD) is an effective anticonvulsant in dogs with idiopathic epilepsy but more evidence is required.
Objective: Evaluate the effect of adding CBD to conventional antiepileptic drugs on seizure control and to report adverse events in dogs with idiopathic epilepsy.
Animals: 51 client-owned dogs diagnosed with idiopathic epilepsy were included in this study. Inclusion criteria required at least two seizures per month documented for 3 months preceding the trial.
Methods: This was a double-blinded, placebo-controlled crossover clinical trial. Twelve dogs were administered 5mg/kg/day oral CBD, and 39 dogs were administered 9mg/kg/day oral CBD. Dogs were randomly assigned to receive either CBD or placebo for 3 months then switched to the opposite oil for 3 months following a one-month washout period. Total number of seizures and seizure days (clusters over a 24-hour period) were recorded. Bloodwork was performed periodically.
Results: At the 9mg/kg/day dose, there was a decrease in number of total seizures during CBD treatment compared to placebo (p = 0.036). There was a significant reduction in seizure days (-24.1%) for dogs receiving 9mg/kg/day CBD compared to placebo (+5.8%) (p = 0.0017). Liver enzymes increased with both doses of CBD administration.
Conclusions: CBD oil treatment resulted in a significant reduction in total seizures and seizure days compared to placebo when administered orally at dose of 9mg/kg/day. This supports further studies investigating the role of CBD in the treatment of idiopathic epilepsy in dogs.
