Rashes in infants without fever: what to know

Look at whether the skin is flat, raised, blistered, scaly, wet or crusted. Tiny red spots in skin folds can follow heat, sweat or friction; dry patches may reflect sensitive skin or eczema. A rash around the nappy area may come from moisture, stool, urine or a new product. Some viral illnesses can begin with skin changes before other symptoms, while chickenpox typically develops itchy spots that become fluid-filled blisters. A rash does not identify one diagnosis by itself.

Keep the baby comfortably cool and dress them in loose, breathable layers. Wash gently with lukewarm water, pat dry, and avoid fragranced soaps, oils and new creams until the cause is clearer. Do not scratch, squeeze blisters or apply adult medicines. For a nappy rash, change nappies promptly and allow short periods of air exposure. Photograph the rash in good light and note when it started, where it spread and any new food, medicine, detergent or skincare product.

Arrange prompt medical advice if the rash spreads quickly, becomes painful, warm, swollen, crusted or blistered, or if your infant feeds poorly, is unusually sleepy, has fewer wet nappies or seems difficult to settle. Seek urgent help for breathing difficulty, facial swelling, repeated vomiting, a seizure, or purple or blood-coloured spots that do not fade when pressed. Any fever in a very young infant warrants urgent clinical advice, even if the rash seems mild.

Ask what the rash most resembles, whether a product or infection could be involved, which moisturiser or cleanser is suitable, and what changes should trigger reassessment. Take the photograph and a list of medicines or products used.