What substance do most antifungals target for their action?

Most antifungals specifically target ergosterol, which is a key component of fungal cell membranes. Ergosterol plays a similar role to cholesterol in human cell membranes but is unique to fungi. This difference allows antifungal medications to selectively disrupt fungal cells without affecting human cells.

Antifungal agents like azoles (e.g., fluconazole, itraconazole), polyenes (e.g., amphotericin B), and allylamines (e.g., terbinafine) exploit this distinction by inhibiting the synthesis or binding to ergosterol, leading to increased cell membrane permeability and ultimately cell death. This mechanism makes targeting ergosterol a highly effective strategy for treating fungal infections, as it directly impacts the integrity and functionality of the fungal cell membrane.