At high concentrations of ketoconazole, the conversion of squalene to methyl sterols was also inhibited. The inhibition of cholesterol synthesis was dose-dependent with an
IC50 approximately 2.8 X 10(-8) M. In parallel to the inhibition of cholesterol synthesis, there was a reciprocal increase in methyl sterol production. The related imidazole antimycotic, clotrimazole, had similar effects, whereas the imidazole anesthetic, etomidate, had little effect on cholesterol synthesis.