What is the first-line topical treatment for tinea corporis?

Topical terbinafine is considered the first-line treatment for tinea corporis, which is a fungal skin infection commonly referred to as ringworm. This effectiveness is largely due to terbinafine's antifungal properties that inhibit the enzyme squalene epoxidase, leading to a disruption in the synthesis of ergosterol, a vital component of fungal cell membranes. As a result, terbinafine directly targets the dermatophyte fungi responsible for tinea corporis, providing effective and rapid relief of symptoms.

While clotrimazole and miconazole are also antifungal agents and can be used to treat tinea corporis, they are generally regarded as second-line options. These azole antifungals work by inhibiting the synthesis of ergosterol as well, but terbinafine tends to have a more favorable efficacy profile for this specific infection. Bacitracin, on the other hand, is not an antifungal; it is primarily effective against bacterial infections and therefore not suitable for treating tinea corporis.