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Nystatin

Brand names: Mycostatin, Nyamyc

Nystatin is an antifungal that treats yeast infections of the mouth (thrush), skin folds, and diaper area.

Brand namesMycostatin, Nyamyc
Type of medicineAntifungal
Prescription?Prescription
ImportantThis page is general information, not a prescription. Don't start, stop, or change a medicine without talking to your provider or pharmacist.

Overview

It stays where it's applied and isn't absorbed much, so side effects are few.

What it's used for

  • Oral thrush
  • Yeast rash in skin folds
  • Yeast diaper rash

How to take it

  • Liquid: swish in the mouth as long as possible, then swallow (or as directed). For babies, use a dropper or swab inside the cheeks.
  • Cream or powder: apply to clean, dry skin.
  • Keep using it for a couple of days after it clears, as directed.

Your dose depends on your health and other medicines. Always follow your prescription label, and ask your pharmacist if anything is unclear.

Side effects

Common side effects

  • Mild nausea or diarrhea (liquid)
  • Skin irritation (cream)
Call 911Swelling of the face, lips, or throat, hives, or trouble breathing
Call 911A blistering, peeling, or widespread red rash, especially with fever

Warnings

  • Thrush that keeps coming back in adults should be checked.

Other medicines, foods, and alcohol

  • No major interactions.

Tell your provider and pharmacist about every medicine, vitamin, and supplement you take.

Pregnancy and breastfeeding

Commonly used in pregnancy and breastfeeding.

Missed doses, overdose, and storage

If you miss a dose

Apply it when you remember, then go back to your usual schedule. Don't apply extra to make up for it.

If someone takes too much

Call Poison Control at 1-800-222-1222 or get help online at poison.org. Call 911 if the person collapses, has a seizure, has trouble breathing, or can't be woken.

Storing it

Store at room temperature, away from heat and moisture (not in the bathroom), and out of reach of children and pets.

Conditions it's used for

Sources

Last updated 2026-11-13.