General Drug Information and Indications

Natamycin ophthalmic suspension for fungal keratitis (keratomycosis) in horses and small animals. Polyene antifungal ophthalmic suspension (natamycin 5%). Mechanism: binds to ergosterol in fungal cell membranes → forms membrane pores → increased permeability and leakage of cellular contents → fungicidal. Active against filamentous fungi (Fusarium, Aspergillus) and yeasts (Candida). Poor corneal penetration; primarily surface active. Key information Natamycin ophthalmic suspension — antifungal. Refrigerate. Shake well. For ophthalmic fungal infections. Store away from light. Do not touch dropper tip to eye.

How to Give this Medication

Ophthalmic suspension: Instill into the conjunctival sac; avoid touching dropper tip to eye or periocular tissue. Shake well before each use. well before each use. Instill 1 drop q1–2h initially, reducing as condition improves. Store at room temperature; protect from light. If a dose is missed Apply the missed dose as soon as you remember. If it is almost time for the next application, skip it and resume the normal schedule. Do not apply extra product to compensate.

Side Effects

Ophthalmic: transient stinging/burning upon instillation. Blurred vision, lid edema, conjunctival chemosis. Foreign body sensation. Systemic absorption minimal with topical use. May cause mild superficial punctate keratopathy.

Precautions

For animals Ophthalmic antifungal — poor corneal penetration; most effective for surface fungal disease. Shake well before use. Assess corneal integrity before use. For people handling this medication Wash hands thoroughly with soap and water after handling. Ophthalmic antifungal — avoid human eye contact. Avoid contact with eyes; if contact occurs, flush with water for 15 minutes and seek medical attention. Wash hands thoroughly with soap and water after handling.

Overdose

Contact your veterinarian if excessive product was applied to the eye. Ophthalmic natamycin is minimally absorbed systemically.

Natacyn Susp dosage forms

ProductStrengthFormSizeType
NATACYN SUSP 5% OP—Suspension1Commercial

Sources

This information is provided for educational purposes and is not a substitute for advice from your veterinarian. Source: Merck Veterinary Manual (merckvetmanual.com); Plumb's Veterinary Drug Handbook (Plumb, D.C., app.plumbs.com)