Nappy rash caused by diarrhoea: what to know

Loose stools may reach more of the skin than formed stools, while frequent bowel movements increase rubbing and cleansing. The result can be red, sore, shiny or broken skin on the buttocks, around the anus, and in nearby folds. This is usually irritant nappy dermatitis, although a persistent rash can have another cause, including thrush. Diarrhoea also raises the risk of dehydration, so the child's drinking, wet nappies and general behaviour matter alongside the skin.

Change nappies promptly after each bowel movement. Rinse with lukewarm water or use fragrance-free wipes, then pat rather than rub. Give short periods without a nappy when practical, and apply a simple protective barrier to clean, dry skin. Avoid scented products, talc, harsh soap and scrubbing. Continue suitable fluids recommended for the child's age; ask a clinician about diarrhoea treatment rather than using an over-the-counter medicine without advice. An emollient can support the skin barrier; see Emollient Therapy for more information.

Seek prompt medical advice if the child is unusually sleepy, has a dry mouth, fewer wet nappies, blood in the stool, repeated vomiting, severe tummy pain or difficulty keeping fluids down. Arrange a skin assessment if the rash is blistered, bleeding, spreading, increasingly painful, associated with fever, or not improving after careful nappy care. A clinician may consider a fungal rash and whether topical antifungal treatment is appropriate.

Could the rash be irritant dermatitis or thrush? What fluid plan suits my child's age? Which barrier product should I use, and how should I apply it if the skin is broken?