Which antifungal agent exerts its action by inhibiting fungal lanosterol 14-alpha-demethylase, thereby blocking ergosterol synthesis?
- A Terbinafine
- B Amphotericin B
- C Itraconazole ✓
- D Flucytosine
Correct answer: C. Itraconazole
Explanation
Azoles including itraconazole, fluconazole, ketoconazole and voriconazole inhibit lanosterol 14-alpha-demethylase, a cytochrome P450 enzyme essential for ergosterol synthesis, making them fungistatic against dermatophytes. Terbinafine acts earlier in the pathway at squalene epoxidase, amphotericin C binds preformed ergosterol in the membrane, and flucytosine is converted to 5-fluorouracil and disrupts nucleic acid synthesis.
Reference: Katzung's Basic and Clinical Pharmacology, 15th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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