10 March 2025
Sylvia Masson
This case presents the clinical journey of Mila, a 6-year-old female mixed-breed Grand Griffon Vendéen, who experienced recurrent, severe episodes of self-directed aggression and dissociative behaviours occurring without identifiable external triggers. Initial considerations included compulsive disorders, pain, and epilepsy, yet standard treatments, including NSAIDs, phenobarbital, and potassium bromide, were ineffective. Detailed behavioural evaluations and key clinical observations – such as maximal pupil dilation, unresponsiveness to external stimuli, and aggression directed at her limbs – supported a working diagnosis of dissociative syndrome, a rare psychiatric condition in dogs analogous to schizophrenia in humans. A brain MRI ruled out structural abnormalities, further supporting the diagnosis. Treatment with fluoxetine and aripiprazole resulted in significant and sustained improvement, reducing the frequency and duration of the episodes to brief occurrences, primarily around evening meals. Mila’s quality of life improved markedly, with her owner reporting no side effects and a return to normal playful behaviours. This case underscores the importance of a structured differential diagnostic approach in veterinary behavioural medicine and highlights the potential of targeted psychopharmacological interventions, including the novel use of aripiprazole in managing complex psychiatric disorders in dogs. The case also sets a precedent for future research and clinical applications in veterinary psychiatry.