tretinoin and Otitis-Externa

The long-term (12 months) oral administration of the aromatic retinoid Ro 10-1670 (etretin) to dogs in relatively high doses of 5.0, 15.0 and 50.0/30.0 mg/kg/day was followed by acanthotic hyperplasia of the epidermis in the external auditory meatus and dose-dependent hypertrophy and/or hyperplasia of the canine ceruminous glands. These morphological changes were accompanied by a secretory stimulation on the ceruminous glands which was slight in the low-dose dogs but in the majority of the high-dose dogs reached a degree that was followed by secondary acute infectious inflammation. The alterations in the external auditory canal ceased almost immediately when treatment of dogs with the aromatic retinoid was stopped but recommenced when it was restarted.

Topics: Acitretin; Animals; Cerumen; Disease Models, Animal; Dog Diseases; Dogs; Ear Canal; Exocrine Glands; Otitis Externa; Tretinoin

Topics: Adult; Cerumen; Darier Disease; Etretinate; Female; Humans; Otitis Externa; Tretinoin