| Pharmacodynamics |
Nystatin is an antibiotic which is both fungistatic and
fungicidal in vitro against a wide variety of yeasts and yeast-like
fungi, including Candida albicans, C. parapsilosis, C. tropicalis, C. guilliermondi, C. pseudotropicalis, C. krusei, Torulopsis glabrata, Tricophyton rubrum, T. mentagrophytes.
Nystatin acts by binding to sterols in the cell membrane of susceptible
species resulting in a change in membrane permeability and the
subsequent leakage of intracellular components. On repeated subculturing
with increasing levels of nystatin, Candida albicans does not
develop resistance to nystatin. Generally, resistance to nystatin does
not develop during therapy. However, other species of Candida (C. tropicalis, C. guilliermondi, C. krusei, and C. stellatoides)
become quite resistant on treatment with nystatin and simultaneously
become cross resistant to amphotericin as well. This resistance is lost
when the antibiotic is removed. Nystatin exhibits no appreciable
activity against bacteria, protozoa, or viruses. |
