Nystop powder is a prescription antifungal medication used to treat yeast infections on the skin, specifically those caused by Candida. Its active ingredient, nystatin, is dispersed in talc at a concentration of 100,000 units per gram and works by killing or stopping the growth of yeast on contact. It’s most commonly applied to moist, warm areas of the body where Candida thrives, like skin folds, feet, and the diaper area in children.
How Nystop Powder Works
Nystatin, the active drug in Nystop, is an antifungal antibiotic that both stops fungi from growing and kills them outright. It’s effective against a wide range of yeast and yeast-like organisms, including several Candida species: C. albicans (the most common culprit in skin yeast infections), C. parapsilosis, C. tropicalis, C. krusei, and others. It also has activity against certain dermatophytes, the fungi responsible for conditions like athlete’s foot and ringworm.
The powder form has a specific advantage over creams and ointments. Because Candida loves moisture, the talc base absorbs sweat and keeps the affected skin dry, which creates an environment that’s hostile to yeast growth while the nystatin does its work. This makes it particularly well-suited for areas where skin rubs together and traps moisture.
Common Uses
Nystop is approved for treating cutaneous and mucocutaneous fungal infections caused by Candida species. In practice, that covers several everyday situations:
- Skin fold infections (intertrigo): The red, raw, sometimes weepy patches that develop under the breasts, in the groin creases, between abdominal folds, or in the armpits. These warm, damp areas are prime territory for Candida overgrowth, and the powder form is ideal because it reduces friction and moisture at the same time.
- Diaper rash caused by yeast: Not all diaper rash is fungal, but when Candida is involved, the rash tends to be bright red with small satellite spots around the edges. Nystop can be used in the diaper area of children, though you should avoid tight-fitting diapers and plastic pants while using it.
- Fungal infections on the feet: The powder can be sprinkled between the toes, on the feet, and even inside socks and shoes to treat and help prevent recurrence of yeast-related foot infections.
How to Apply It
The standard recommendation is to apply Nystop to the affected skin two or three times a day for both adults and children. You should use enough powder to lightly cover the entire affected area. There’s no need to rub it in aggressively; a dusting that coats the skin is sufficient.
For foot infections, sprinkle the powder between your toes and across the soles, then add some inside your socks and shoes before putting them on. This helps keep the area dry throughout the day and maintains antifungal contact.
One important rule: don’t cover the treated area with airtight bandages, plastic wrap, or any occlusive dressing. Sealing the powder under a non-breathable barrier can increase irritation and defeats the purpose of using a drying powder in the first place. The whole point is to let air reach the skin.
How Long Treatment Takes
Most topical yeast infections begin improving within a few days, but you should continue using Nystop for the full course your prescriber recommends, even after the rash looks better. Stopping too early is a common reason for the infection to come back. Candida can persist on the skin surface even when visible symptoms have cleared, and it takes continued treatment to fully eliminate the organism.
Side Effects and Precautions
Nystop is generally well tolerated. The most commonly reported side effect is mild skin irritation at the application site. Serious reactions are rare. However, if you have a known allergy to nystatin, you should not use this product.
Because the powder base is talc, it’s worth being careful not to inhale it during application, especially when using it on children. Tilt the container close to the skin and dust gently rather than shaking it from a height.
Storage
Keep Nystop at room temperature, between 59°F and 86°F (15°C to 30°C). Avoid storing it in places that get excessively hot, such as a car glove compartment in summer or near a radiator. Heat above 104°F (40°C) can degrade the medication.