Randomized, controlled clinical trial of the efficacy of fluoxetine for treatment of compulsive disorders in dogs.

Objective: To evaluate efficacy of fluoxetine hydrochloride for treatment of compulsive disorders in dogs.

Design: Randomized, controlled clinical trial.

Animals: 63 dogs with compulsive disorders.

Procedures: The diagnosis was confirmed on the basis of analysis of videotapes of the dogs' behavior by 3 veterinary behaviorists, results of physical examination and clinicopathologic testing, and, when necessary, telephone interviews with owners. Dogs were randomly assigned to treatment with fluoxetine (1 to 2 mg/kg [0.45 to 0.9 mg/lb], PO, q 24 h) or a placebo. Owners did not receive any advice regarding behavioral or environmental modifications. Severity of episodes was measured through telephone interviews every 2 weeks and on the basis of a daily diary kept by each owner.

Results: 42 days after the initiation of treatment, the proportion of dogs with a decrease in severity of the compulsive disorder, as reported by the owners, was significantly higher for dogs treated with fluoxetine than for control dogs, and dogs treated with fluoxetine were significantly more likely (odds ratio, 8.7) to have a decrease in severity of the compulsive disorder. However, mean number and duration of compulsive episodes, as determined from daily diary entries, did not differ significantly between groups. The most common adverse effects were decreased appetite and mild lethargy.

Conclusions And Clinical Relevance: Results suggested that fluoxetine may be efficacious in the treatment of compulsive disorders in dogs, although results were equivocal. The present study did not examine whether fluoxetine was more efficacious than or synergistic with behavioral and environment modifications.