In vitro efficacy of shampoos containing miconazole, ketoconazole, climbazole or accelerated hydrogen peroxide against Microsporum canis and Trichophyton species

Abstract

Objectives The objective was to evaluate the antifungal efficacy of shampoo formulations of ketoconazole, miconazole or climbazole and accelerated hydrogen peroxide wash/rinse against Microsporum canis and Trichophyton species spores. Methods Lime sulfur (1:16)-treated control, enilconazole (1:100)-treated control, accelerated hydrogen peroxide (AHP 7%) 1:20 and a 1:10 dilution of shampoo formulations of miconazole 2%, miconazole 2%/chlorhexidine gluconate 2–2.3%, ketoconazole 1%/chlorhexidine 2%, climbazole 0.5%/chlorhexidine 3% and sterile water-untreated control were tested in three experiments. In the first, a suspension of infective spores and hair/scale fragments was incubated with a 1:10, 1:5 and 1:1 dilution of spores to test solutions for 10 mins. In the second, toothbrushes containing infected cat hair in the bristles were soaked and agitated in test solutions for 10 mins, rinsed, dried and then fungal cultured (n = 12×). In the third, a 3 min contact time combined with an AHP rinse was tested (n = 10×). Good efficacy was defined as no growth. Results Water controls grew >300 colony-forming units/plate and all toothbrushes were culture-positive prior to testing. For the suspension tests, all test products showed good efficacy. Miconazole 2%, ketoconazole 1% and AHP showed good efficacy after a 10 min contact time. Good efficacy was achieved with a shorter contact time (3 mins) only if combined with an AHP rinse. Conclusions and relevance Lime sulfur and enilconazole continued to show good efficacy. In countries or situations where these products cannot be used, shampoos containing ketoconazole, miconazole or climbazole are alternative haircoat disinfectants, with a 10 min contact time or 3 mins if combined with an AHP rinse.