Ototoxicity of Common Topical Antimycotic Preparations
April 2000
in “
The Laryngoscope
”
TLDR Clotrimazole, miconazole, and tolnaftate are likely safe, but gentian violet is risky.
The study investigated the ototoxic effects of five topical antimycotic agents—clotrimazole, miconazole, nystatin, tolnaftate, and gentian violet—on guinea pigs by measuring hair cell loss. Results showed that clotrimazole, miconazole, and tolnaftate did not cause hair cell loss in the first two cochlear turns, and nystatin showed no evidence of ototoxicity, although it left a persistent residue. Gentian violet, however, caused significant vestibular damage and middle ear inflammation, preventing accurate hair cell counts. The study concluded that while extrapolating to humans requires caution, clotrimazole, miconazole, and tolnaftate appear safe, whereas gentian violet poses a risk of severe damage. The residue from nystatin highlights the importance of considering both active ingredients and vehicles in safety evaluations.