Nyastatin

Nystatin is a polyene antibiotic, and its structure, chemistry, mechanism of action, and resistance profile resemble those of amphotericin B. Its use is restricted to topical treatment of Candida infections because of its systemic toxicity. The drug is negligibly absorbed from the gastrointestinal tract It is administered as an oral agent (“swish and swallow” or “swish and spit”) for the topical treatment of oral candidiasis. Excretion in the feces is nearly quantitative. Adverse effects are rare because of its lack of absorption orally, but nausea and vomiting occasionally occur that disrupts fungal membranes by binding to ergosterol. Nystatin is commonly used topically to suppress local Candida infections and has been used orally to eradicate gastrointestinal fungi in patients with impaired defense mechanisms. Other topical antifungal agents that are widely used include the azole compounds miconazole, clotrimazole, and several others