Infant rash with no fever: what to know

Dry, itchy, rough patches can fit eczema. Redness in warm skin folds may reflect moisture and friction, while spots under a nappy may be contact irritation. Hives are raised, changeable welts that can follow an infection, food, medicine, or contact exposure. Small spots, crusting, blisters, or pus can point to a different problem. No fever does not rule out infection, and a baby's age, feeding, breathing, and behaviour are as useful as the rash itself. Do not assume a food allergy from a rash alone.

Look at the rash in natural light and check whether it is flat, raised, scaly, wet, blistered, or bruised-looking. Stop recently introduced fragranced products and dress your infant in soft, breathable layers. Use a plain moisturiser for dry skin if it has previously been recommended, and keep nails short to reduce scratching. Avoid squeezing spots or applying leftover prescription creams. Keep a note of new foods, medicines, detergents, fabrics, and animal contact, and photograph changes for a clinician.

Call emergency services for breathing difficulty, wheezing, swelling of the lips or tongue, collapse, or unusual difficulty waking. Seek urgent assessment when a rash does not fade under pressure, looks like bruising, blisters widely, causes severe pain, or spreads quickly. Obtain same-day advice for poor feeding, fewer wet nappies, marked sleepiness, pus, spreading warmth, or a new rash after medicine or food. A persistent or recurrent rash deserves a routine review even when your infant seems comfortable.

What features suggest eczema, contact irritation, hives, or infection? Could anything recently touching or eaten by my infant be relevant? What skin products are suitable, and when should the rash be reassessed?