What class of medication is amphotericin B primarily used to treat?

Amphotericin B is primarily used to treat fungal infections due to its effectiveness against a broad spectrum of fungi. It functions by binding to ergosterol, a key component of fungal cell membranes, which leads to increased membrane permeability and ultimately causes cell death. This mechanism makes it particularly useful for treating serious fungal infections, such as those caused by Candida and Aspergillus species, and is often utilized in immunocompromised patients who are at higher risk of developing such infections.

The other options represent different categories of infections that require specific types of treatments. Bacterial infections are typically treated with antibiotics, viral infections are managed with antiviral medications, and parasitic infections involve antiparasitic drugs. Since amphotericin B does not exhibit efficacy against bacteria, viruses, or parasites, its classification as a treatment for fungal infections is what makes it the appropriate choice in this context.