Unusual response of a yeast to imidazole antifungals.

Thiamin was shown to relieve preferentially the toxicity of econazole for a yeast which showed an unusual response to imidazole drugs. The possible role of this vitamin in the response of the yeast to imidazoles is discussed. An investigation of the effect of a second exposure of yeasts to imidazole drugs showed that there is an increase in sensitivity when the cells are transferred directly to fresh medium containing the same concentrations of the drug, and a decrease in sensitivity following transfer via drug-free medium.