The aim of the study was to assess the efficacy and tolerability of fluoxetine treatment of acral lick dermatitis (ALD) in dogs and to investigate ALD as an animal model of obsessive-compulsive disorder (OCD). Sixty-three dogs with ALD were treated with fluoxetine 20 mg daily, or placebo, for 6 weeks. In the fluoxetine group, owners rated both appearance of the lesion (t = 10.2, df = 29, P < 0.0001) and licking behavior (t = 10.2, df = 29, P < 0.0001) as significantly improved by the end of the trial. Veterinarian-rated pre- and post-treatment photographs showed statistically significant improvement in the fluoxetine group (mean = 2.55). There were no significant changes in the placebo group as rated by owners and veterinarians. These results demonstrate the efficacy of fluoxetine in the treatment of ALD and lend further support to ALD as an animal model of OCD.