A rash can look alarming on a baby, especially when it appears suddenly and your child is too young to tell you what feels wrong. The reassuring part is that many baby rashes are mild and settle with simple care. The important part is learning to look beyond colour alone: where the rash is, whether it is raised, dry, blistered or crusty, and—most importantly—how your baby is behaving.
This guide can help you identify common baby rashes, but appearance alone is not always enough for a safe diagnosis. If your baby seems unwell or you are worried, seek medical advice rather than waiting for the skin to change.
Start with the pattern, not just the colour
Before comparing baby skin rash types, check four clues: location, texture, timing and your baby’s general condition. A rash limited to the nappy area suggests something different from dry patches on the cheeks or tiny bumps in warm skin folds. Ask whether it appeared after heat, a new product, an illness or several hours in a wet nappy.
On brown or black skin, redness can be less obvious. Pay attention to texture, swelling, feeding, alertness, breathing and temperature.
Common newborn rashes that are usually harmless
Milia
Milia are tiny white or pale bumps, often seen on a newborn’s nose, cheeks or forehead. They do not need squeezing, scrubbing or medicated cream and usually clear naturally. Among newborn rash causes, milia are one of the least concerning when a baby is otherwise well.
Erythema toxicum
This blotchy rash often appears during the first few days of life. It can come and go across the face, body, upper arms or thighs while the baby remains comfortable and feeds normally. Despite its dramatic name, erythema toxicum is generally harmless and usually disappears without treatment.
A quick guide to common baby rash patterns
• Nappy rash: sore, red, pink or darker-looking skin mainly under the nappy.
• Eczema: dry, itchy, cracked or scaly patches that may repeatedly flare.
• Heat rash: tiny raised spots with an itchy or prickly feeling, often after overheating.
• Hives: raised itchy bumps or patches that can appear suddenly and change shape.
• Impetigo: sores or blisters that burst and leave golden-brown crusty patches.
Nappy rash: irritation where moisture and friction collect
Nappy rash can make the skin look sore or feel hot. Contact with urine or stool, rubbing, fragranced products and sometimes thrush can contribute. Change wet or dirty nappies promptly, clean gently with water or fragrance-free, alcohol-free wipes, pat the skin dry and allow nappy-free time when practical. A pharmacist can advise on barrier cream.
See a health visitor or GP if the rash worsens, spreads, does not improve, or your baby seems very uncomfortable.
Eczema in babies: dry, itchy and repeatedly inflamed
Atopic eczema can make a baby’s skin itchy, dry, cracked, scaly or crusty. In babies and toddlers it commonly affects the face, although it can occur elsewhere. Its colour varies with skin tone and may look red, purple, grey, lighter or darker than surrounding skin.
A baby’s eczema flare usually behaves differently from a short-lived heat rash because the dryness and itching tend to recur. Avoid heavily fragranced skincare and speak to a GP if you think your baby has eczema, especially if the skin is weeping, crusting, bleeding or causing significant discomfort.
Heat rash and hives: two raised rashes with different clues
Heat rash, also called prickly heat, causes small raised spots and an itchy or prickling sensation. It often develops when a baby becomes hot and sweaty. Move your baby somewhere cooler, use light clothing and bedding, and avoid perfumed creams. A useful real-world clue is timing: tiny bumps around the neck, chest or skin folds after a warm nap or an overdressed outing make heat rash more likely.
Hives form raised itchy bumps or patches that can appear anywhere and may spread. If hives occur alone and your baby is otherwise well, ask a pharmacist or clinician what is suitable for your child’s age. If there is sudden swelling of the lips, mouth, throat or tongue, difficulty breathing, trouble swallowing, floppiness or unusual unresponsiveness, call 999 immediately.
Impetigo and viral rashes need a closer look
Impetigo is infectious and often begins with sores or blisters that burst and leave golden-brown crusts, commonly around the nose and mouth or on the hands. For a baby aged 11 months or younger with suspected impetigo, NHS guidance advises seeing a GP.
Some rashes arrive with an infection. Hand, foot and mouth disease can cause mouth ulcers plus raised spots or blisters on the hands and feet. Measles usually starts with cold-like symptoms and a high temperature, followed by a rash beginning on the face or behind the ears and spreading down the body. If you suspect measles, contact the GP surgery before attending because it spreads.
When to worry about a baby rash
Call 999 or go to A&E if your baby is unwell and the rash looks like bruising or bleeding under the skin and does not fade when a clear glass is pressed firmly against it. Serious warning signs also include difficulty breathing, sudden swelling around the mouth or throat, marked drowsiness, unusual unresponsiveness, a stiff neck, or pale, blue, grey or blotchy skin.
Seek urgent GP help or contact NHS 111 if a baby under 3 months has a temperature of 38C or higher, or if you are worried about a rash and do not know what to do. Do not rely on the glass test alone: a serious infection can occur without a non-blanching rash.
FAQ
Can I identify a baby rash from a photo?
A photo can help you compare general patterns, but lighting and skin tone can change how a rash looks. Texture, temperature, feeding, alertness and other symptoms matter too. Use photos as a guide, not a diagnosis.
Should I do the glass test on every rash?
The glass test can help identify a non-blanching rash, but a rash that fades under pressure does not prove that a baby is well. If your baby seems seriously ill, seek urgent help regardless of the result.
How long should I watch a mild rash at home?
It depends on the likely cause and your baby’s age. Harmless newborn rashes may settle without treatment, while nappy rash should improve with careful skin care. If a rash spreads, worsens, persists or comes with fever or behavioural changes, get professional advice.
What should I do first if I am unsure?
Check your baby’s temperature and general behaviour, note where the rash began, and avoid trying several new creams at once. A pharmacist, health visitor, GP or NHS 111 can help you decide what to do next.
Recognise the pattern, but watch the baby
Learning the usual patterns can make common baby rashes less frightening: milia are tiny and harmless, nappy rash stays mainly in the nappy area, eczema is dry and itchy, heat rash is prickly, hives are raised, and impetigo tends to crust. When deciding when to worry about a baby rash, feeding, breathing, temperature and responsiveness matter more than finding the perfect label. If your baby looks or behaves unusually unwell, seek medical help promptly.