HomeSearch by AntimicrobialNystatin
Antimicrobial Name: Nystatin
CAS Number: 1400-61-9
Functional Category: Antifungal
Molecular Weight: 926.09
Mechanism of Action: Like amphotericin B and natamycin, nystatin binds to ergosterol, a major component of the fungal cell membrane. When present in sufficient concentrations, it forms pores in the membrane that lead to K+ leakage and death of the fungus. Ergosterol is fairly unique to fungi, so the drug does not have such catastrophic effects on animals.
Chemical Formula:



4.0 mg/ml at 28 °C in water

11.2 mg/ml at 28 °C in methanol

1.2 mg/ml at 28 °C in ethanol

1.23 mg/ml at 28 °C in carbon tetrachloride

0.48 mg/ml at 28 °C in chloroform

0.28 mg/ml at 28 °C in benzene

8.75 mg/ml at 28 °C in ethylene glycol


Melting point:

250 °C, 160 °C (dec)


Nystatin is a polyene antifungal drug to which many molds and yeast infections are sensitive, including Candida. Due to its toxicity profile, there are currently no injectable formulations of this drug on the US market. However, nystatin may be safely given orally as well as applied topically due to its minimal absorption through mucocutaneous membranes such as the gut and the skin.