Nystatin: What It Is, How It Works, and When It's Used

When you have a nystatin, a topical antifungal medication used to treat fungal infections caused by Candida species. Also known as nilstat, it doesn’t get absorbed into your bloodstream — it works right where you apply it. That’s why it’s perfect for infections in the mouth, skin, or vagina, but not for systemic fungal problems. You won’t find nystatin in pills you swallow for a full-body infection. Instead, it’s in creams, ointments, powders, and oral suspensions. It’s been around since the 1950s, and doctors still reach for it because it’s safe, cheap, and rarely causes side effects.

Nystatin targets Candida, a type of yeast that naturally lives on the skin and in the digestive tract. When it overgrows — thanks to antibiotics, diabetes, or a weak immune system — it causes thrush, diaper rash, or vaginal itching. Unlike strong antifungals like fluconazole, nystatin doesn’t mess with liver enzymes or interact with most other drugs. That’s why it’s often the first choice for babies, pregnant women, and older adults who can’t handle stronger meds. It’s also used in people with HIV or those on long-term steroids, where fungal infections are common but drug interactions are risky. You’ll see it in the same posts as oral thrush, a fungal infection in the mouth that causes white patches and discomfort, because that’s one of its most frequent uses. And if you’ve ever used a cream for a persistent rash that didn’t respond to hydrocortisone, chances are it was nystatin doing the heavy lifting.

What you won’t find in these posts is nystatin being used for bacterial infections, athlete’s foot caused by dermatophytes, or toenail fungus. It only works on Candida. That’s why some people think it didn’t work for them — they were treating the wrong thing. The real value of nystatin lies in knowing exactly when to use it and when to switch. If your thrush doesn’t clear up in a week or two, your doctor might switch you to an oral antifungal. But for mild cases? Nystatin is still the go-to.

You’ll find posts here about how pharmacists recommend it, how it compares to other antifungals, and how to use it correctly — whether it’s a mouth rinse you spit out or a cream you apply twice daily. There’s no magic here. Just clear, practical info on how to get rid of a stubborn yeast infection without side effects or complications. What follows are real cases, real comparisons, and real advice from people who’ve been there — and figured out what actually works.