Investigation of the clinical efficacy of 0.2% topical stannous fluoride for the treatment of canine superficial pyoderma: a prospective, randomized, double-blinded, placebo-controlled trial.

Stannous fluoride (SF) is an antibacterial compound that has been successfully used to treat gingivitis in people and dogs, and cutaneous bacterial infections in horses. The purpose of this prospective, double-blinded, placebo-controlled clinical trial was to investigate the efficacy of 0.2% SF spray (BacDerm; Emerald 3 Enterprises Inc., Camdenton, MO, USA) for the treatment of canine superficial pyoderma. Twenty-six privately owned dogs with bacterial skin infections diagnosed on clinical signs, cytology and aerobic culture were enrolled. Dogs were randomly assigned to vehicle only or active ingredient treatment groups. The product was applied topically to affected areas once daily for 28 days, with assessments at days 0, 14, 28 and 42. Clinical and cytological evaluations were performed by the same investigators at each visit. Owners scored the improvement of hair coat, odour, pruritus and overall improvement at each recheck. Linear mixed models showed significant effects of treatment (P < 0.0001) and time (P = 0.0037) for investigator's scores, and a significant time effect for owners' haircoat (P = 0.0077) and odour (P = 0.0170) improvement scores. Dogs in both placebo and SF groups showed some improvement over time, and the investigator's scores on days 0 and 28 were not significantly different between groups for both (t-test P > 0.05). Spearman's rho correlation coefficients revealed a significant negative correlation between investigator's scores and all categories of owners' assessment scores in dogs of both groups. Although some dogs improved on SF, this study does not support the use of 0.2% SF as sole therapy for canine superficial pyoderma.