Nystatin is a polyene antifungal antibiotic obtained from Streptomyces noursei. Structural formula:

C 47 H 75 NO 17        MW 926.13      CAS-1400-61-9

MYCOSTATIN® (nystatin lozenges, USP) PASTILLES are round, light to dark gold-colored troches designed to dissolve slowly in the mouth. Each MYCOSTATIN PASTILLE provides 200,000 units nystatin. Inactive ingredients: anise oil, cinnamon oil, gelatin, sucrose, and other ingredients.

Nystatin is both fungistatic and fungicidal in vitro against a wide variety of yeasts and yeast-like fungi. Candida albicans demonstrates no significant resistance to nystatin in vitro on repeated subculture in increasing levels of nystatin; other Candida species become quite resistant. Generally, resistance does not develop in vivo . Nystatin acts by binding to sterols in the cell membrane of susceptible fungi with a resultant change in membrane permeability allowing leakage of intracellular components. Nystatin exhibits no activity against bacteria, protozoa, trichomonads, or viruses.

Pharmacokinetics:   Gastrointestinal absorption of nystatin is insignificant. Most orally administered nystatin is passed unchanged in the stool. Significant concentrations of nystatin may appear occasionally in the plasma of patients with renal insufficiency during oral therapy with conventional dosage forms.

Mean nystatin concentrations in excess of those required in vitro to inhibit growth of clinically significant Candida persisted in saliva for approximately two hours after the start of oral dissolution of two MYCOSTATIN PASTILLES (400,000 units nystatin) administered simultaneously to 12 healthy volunteers.