nystatin (oral)



Trade Name(s)

  • Mycostatin

Ther. Class.


For other nystatin dosage forms, see antifungals (topical) and antifungals (vaginal)


  • Oral suspension: Local treatment of oropharyngeal candidiasis.
  •  Oral tablet: Treatment of nonesophageal mucus membrane gastrointestinal candidiasis.


Binds to fungal cell membrane, allowing leakage of cellular contents.

Therapeutic Effect(s):

Fungistatic or fungicidal action.


Active against most pathogenic Candida species, including C. albicans.


Absorption: Poorly absorbed; action is primarily local.

Distribution: Unknown.

Metabolism and Excretion: Excreted unchanged in the feces after oral administration.

Half-life: Unknown.

TIME/ACTION PROFILE (antifungal effects)

PO24–72 hr unknownunknown


Contraindicated in:

  • Hypersensitivity;
  • Some products may contain ethyl alcohol or benzyl alcohol–avoid use in patients who may be hypersensitive to or intolerant of these additives.

Use Cautiously in:

Denture wearers (dentures require soaking in nystatin suspension).

Adverse Reactions/Side Effects

Derm: contact dermatitis, STEVENS-JOHNSON SYNDROME

GI: diarrhea, nausea, stomach pain (large doses), vomiting

* CAPITALS indicate life-threatening.
Underline indicate most frequent.



None significant.


Oropharyngeal Candidiasis

PO (Adults and Children): 400,000–600,000 units 4 times daily as oral suspension.

PO Infants: 200,000 units 4 times daily or 100,000 units to each side of the mouth 4 times daily.

PO (Neonates , Premature, and Low Birth Weight): 100,000 units 4 times daily or 50,000 units to each side of the mouth 4 times a day.

Gastrointestinal Candidiasis

PO (Adults): 500,000–1,000,000 units 3 times daily. Continue for ≥48 hr after clinical cure to prevent relapse.

Availability (generic available)

Oral suspension: 100,000 units/mL

Oral tablets: 500,000 units


  • Inspect oral mucous membranes before and frequently during therapy. Increased irritation of mucous membranes may indicate need to discontinue medication.


  • Do not confuse nystatin with HMG-CoA reductase inhibitors ("statins").
  • PO Administer suspension by placing ½ of dose in each side of mouth. Patient should hold suspension in mouth or swish throughout mouth for several min before swallowing, then gargle and swallow. Use calibrated measuring device for liquid doses. Shake well before administration. Pedi:  For neonates and infants, paint suspension into recesses of the mouth. Avoid feedings for 5–10 min following administration or administer after meals.

Patient/Family Teaching

  • Instruct patient to take medication as directed. If a dose is missed, take as soon as remembered but not if almost time for next dose. Do not double doses. Therapy should be continued for at least 2 days after symptoms subside.
  • Pedi:  Instruct parents or caregivers of infants and children on correct dose and administration. Remind them to use only the measuring device dispensed with the product.
  • Advise patient to report increased irritation of mucous membranes or lack of therapeutic response to health care professional.
  • Rep:  Advise females of reproductive potential to notify health care professional if pregnancy is planned or suspected or if breastfeeding.

Evaluation/Desired Outcomes

  • Decrease in stomatitis.
  • Treatment of intestinal candidiasis.