A 40-year-old woman with onychomycosis is prescribed an allylamine antifungal that inhibits squalene epoxidase, leading to squalene accumulation and ergosterol depletion in fungal cells. Which drug is this?
- A Fluconazole
- B Amphotericin B
- C Terbinafine ✓
- D Caspofungin
Correct answer: C. Terbinafine
Explanation
Terbinafine is an allylamine that inhibits squalene epoxidase, causing toxic squalene accumulation and ergosterol deficiency in fungal membranes. It is fungicidal against dermatophytes and is the preferred oral agent for onychomycosis. Fluconazole inhibits CYP450-dependent lanosterol demethylase. Amphotericin C binds ergosterol directly. Caspofungin inhibits beta-1,3-glucan synthase.
Reference: Katzung Basic and Clinical Pharmacology, 15th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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