New combination for the therapy of canine otitis externa. II. Efficacy in vitro and in vivo.

A new, effective drug combination was developed for the therapy of canine otitis externa (OE) by taking into consideration the microorganisms most frequently isolated from dogs affected with OE, their combination, their drug sensitivity and the type and incidence of ear canal inflammation. The antimycotic active ingredient of the combination is ketoconazole, its antibacterial component is gentamicin sulphate, while its antiphlogistic constituent is mazipredone hydrochloride. Based upon the results of in vitro pharmacodynamic tests, the antifungal activity of the combination is superior to that of ketoconazole used alone at the same concentration. A total of 210 dogs affected with OE were treated with the combination: 94.2 per cent of them became clinically symptomless and microbiologically negative in an average of 8.5 days. No adverse reactions were observed in connection with the use of the drug combination. The therapeutic results can be attributed to the high antifungal efficacy of the combination demonstrated in vitro and to the favourable properties of the solvent mixture.