Nystatin is widely used as an antifungal medication to treat infections caused by Candida species. It is particularly effective in managing oral thrush, a common condition in infants, immunocompromised individuals, and those using inhaled corticosteroids. Additionally, it is applied topically to treat cutaneous candidiasis, such as fungal infections of the skin, nails, and mucous membranes. In some cases, it is used intravaginally to treat vaginal yeast infections. Nystatin works by binding to ergosterol in the fungal cell membrane, disrupting its integrity and leading to cell death. It is not absorbed significantly through the skin or mucous membranes, making it a safe option for localized treatment.