Proactive Treatment of Canine Allergic Otitis Externa With Hydrocortisone Aceponate: A Retrospective Observational...

Allergic otitis externa is common in dogs and recurrence may lead to repeated consultations and antimicrobial use. Long-term data on proactive topical corticosteroid maintenance are limited.

To describe 12-month relapse frequency in dogs with allergic otitis externa receiving proactive hydrocortisone aceponate maintenance therapy and compare consecutive-day and non-consecutive-day schedules.

Medical records of client-owned dogs prescribed hydrocortisone aceponate ear spray were retrospectively reviewed. Maintenance started after clinical and cytological remission. Only dogs with confirmed continuation, stable concomitant allergy management and complete 12-month outcome data were included. Relapse was defined as recurrent otitis externa requiring veterinary examination, cytology and additional otic treatment. Dogs were grouped by schedule: Protocol 1, two consecutive days; and Protocol 2, two non-consecutive days weekly. Outcomes were compared using Fisher exact and Mann-Whitney U tests.

Seventy-one dogs were included; 36 in Protocol 1 and 35 received Protocol 2. During 12 months, 50/71 dogs (70.4%) had no relapse, 12/71 (16.9%) had one relapse and 9/71 (12.7%) had multiple relapses. At least one relapse occurred in 9/36 dogs (25.0%) in Protocol 1 and 12/35 (34.3%) receiving Protocol 2 (p = 0.443). Multiple relapses occurred in 2/36 (5.6%) and 7/35 (20.0%) dogs, respectively (p = 0.085). Relapse counts did not differ significantly between protocols (p = 0.290).

Most dogs had no relapse or only one relapse during proactive hydrocortisone aceponate maintenance. No statistically significant difference was detected between schedules, but equivalence or non-inferiority cannot be concluded.