NYSTATIN

Chemistry - A polyene antifungal antibiotic produced by Streptomyces noursei, nystatin occurs asa yellow to light tan, hygroscopic powder having a cereal-like odor. It is very slightly soluble inwater and slightly to sparingly soluble in alcohol. One mg of nystatin contains not less than 4400
Units of activity. According to the USP, nystatin used in the preparation of oral suspensions shouldnot contain less than 5000 Units per mg.

Storage, Stability, Compatibility

Nystatin tablets and oral suspension should be stored at roomtemperature (15-30°C) in tight, light-resistant containers. Avoid freezing the oral suspension orexposing to temperatures greater than 40°C.
Nystatin deteriorates when exposed to heat, light, air or moisture.

Pharmacology - NYSTATIN

Nystatin has a mechanism of action similar to that of amphotericin B. It binds tosterols in the membrane of the fungal cell where it alters the permeability of the membrane allowingintracellular potassium and other cellular constituents to "leak out".
Nystatin has activity against a variety of fungal organisms, but is clinically used against topical, oropharyngeal and gastrointestinal Candida infections.

Uses, Indications

Nystatin is used orally primarily for the treatment of oral or gastrointestinaltract Candida infections in dogs, cats and birds. It has also been used in other species for the sameindications, but less commonly.
Nystatin is also used for the topical treatment of Candidal (Monilial) skin infections. It is aprincipal ingredient in the well-known proprietary product, Panolog®.

Pharmacokinetics - NYSTATIN

Nystatin is not measurably absorbed after oral administration and is almostentirely excreted unchanged in the feces. The drug is not used parenterally because it is reportedlyextremely toxic to internal tissues.

Contraindications, Precautions, Reproductive Safety

Nystatin is contraindicated in patientswith known hypersensitivity to it.
Although the safety of the drug during pregnancy has not been firmly established, the lack ofappreciable absorption or case reports associating the drug with teratogenic effects appear to makeit safe to use.

Adverse Effects, Warnings

Occasionally, nystatin may cause GI upset (anorexia, vomiting, diarrhea) when administered in high dosages. Rarely, hypersensitivity reactions have been reported inhumans.

Overdosage, Acute Toxicity

Because the drug is not absorbed after oral administration, acutetoxicity after an oral overdose is extremely unlikely, but transient GI distress may result.

Drug Interactions

The veterinary-approved product for chickens and turkeys (Myco-20®¯Solvay) should not be administered with tetracycline products. It has a high calcium contentin its vehicle that may prevent oral absorption of tetracycline.