What causes diaper rash?

Soiled diapers, whether cloth or disposable, create a warm, damp environment that can cause irritation and promote infection.

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Other factors that may contribute to diaper rash:

Causes urine and feces

Contact with urine and feces:

Extended exposure to urine and feces can irritate the skin. Both urine and feces cause moisture that comes into contact with the skin, making the skin more prone to damage and irritation. Digestive enzymes found in feces may also contribute to diaper rash. While ammonia (a chemical in urine) can irritate the skin, the levels found in a baby's urine are usually not enough to cause a diaper rash, although this can exacerbate already irritated and inflamed skin.

Causes  friction and rubbing

Friction and rubbing:

Whether it is tight-fitting diapers chafing the skin or skin-to-skin contact within skin folds in the diaper area, friction and rubbing contributes to diaper rash. Irritation is worsened when the skin is wet.

Causes pre-existing skin conditions

Pre-existing skin conditions

like eczema and atopic dermatitis (a type of eczema) may make infants and children more prone to develop a diaper rash.

Causes irritating chemicals

Contact with irritating chemicals:

Certain chemicals found in products such as fabric softeners, detergents, baby lotions, fragrances, soaps, and scented baby wipes can irritate the skin and should be avoided. Talk to your doctor or pharmacist about which products to stay away from.

Causes antibiotic use

Antibiotic use:

Antibiotic use can upset the normal balance of “good and bad” bacteria, which typically keeps certain organisms, such as yeast, in check. Without the presence of good bacteria, yeast can grow more abundantly and cause a yeast infection in the diaper area, even in boys. A breastfed baby may even be affected by their mom taking antibiotics.

Causes infections


The moist, dark, and closed environment created by a diaper is a perfect breeding ground for bacterial or yeast infections (e.g. Candida) on the skin. These types of infections are more frequent in babies who have a diaper rash. Signs of infection are blisters, pus, red bumps in the creases of the skin, or severely swollen red areas that do not disappear with regular baby diaper rash treatments like zinc oxide cream.