The rash that cannot wait

The NHS's emergency list for a child who is unwell with a rash is short and specific. Call 999 or go to A&E now if your child has a rash and any of:

"the rash looks like small bruises or bleeding under the skin and does not fade when you press a glass against it"
a stiff neck, or being bothered by light
seeming confused or agitated, or not responding as they usually do
difficulty breathing, breathlessness or very fast breathing, including grunting noises or the tummy sucking in under the ribs
skin, lips or tongue looking pale, blue, grey or blotchy
sudden swelling of the lips, mouth, throat or tongue, a tight throat, or struggling to swallow

NICE's fever guideline reinforces the first of those: consider meningococcal disease "in any child with fever and a non-blanching rash, particularly if any of the following features are present: an ill-looking child, lesions larger than 2 mm in diameter, a capillary refill time of 3 seconds or longer, neck stiffness." A non-blanching rash is a red feature in the NICE traffic light system.

Two practical points from the NHS. On brown and black skin, "it may be easier to see the rash or colour changes on the soles of the feet, palms, lips, tongue and inside the eyelids." And a child "might not have a high temperature but still be seriously unwell" — the absence of fever is not reassurance.

Ask for an urgent GP appointment or call 111 if your child has a rash you are worried about and are not sure what to do, feels hotter than usual or is shivering, or is under 3 months with a temperature of 38C (100.4F), or 3 months or older with 39C (102.2F) or higher.

Rashes that come with a temperature

Slapped cheek syndrome

The NHS describes the first sign as "usually feeling unwell for a few days", followed by a bright rash on one or both cheeks. A lighter, raised, sometimes itchy rash can then appear on the body. The cheek rash is the giveaway. It "usually fades within 1 to 3 weeks, but it can sometimes last for longer, especially if you're hot or stressed", and it can usually be managed at home without seeing a GP.

Hand, foot and mouth disease

Blisters on the hands and feet with ulcers in the mouth. The NHS says it "usually gets better on its own in 7 to 10 days. You cannot take antibiotics or other medicines to cure it." Spots can look pink, red or darker than surrounding skin depending on skin tone, and blisters may be grey or lighter than the surrounding skin and painful. A pharmacist can advise on mouth ulcer gels suitable for children. The mouth ulcers, not the rash, are what stop children eating and drinking — watch fluids rather than spots.

Chickenpox

An itchy, spotty rash that can be anywhere on the body, "including inside the mouth and around the genitals, which can be painful". The NHS describes three stages, with new spots appearing while others are already blistering or scabbing. A high temperature, aches and loss of appetite can come before or after the rash.

Scarlet fever

This one needs a doctor. The NHS says the first signs "can be flu-like symptoms, including a high temperature, a sore throat and swollen neck glands", followed by a rash that feels rough and raised. On white skin it looks pink or red; on brown and black skin the colour change may be hard to see, but "you can still feel the rash and see the raised bumps." The rash does not appear on the face, though the cheeks can look flushed, and the skin sometimes peels like sunburn as it fades. See a GP — and call ahead, because it spreads very easily.

Measles

Measles "usually starts with cold-like symptoms, followed by a rash a few days later", with small white spots sometimes appearing inside the cheeks and on the back of the lips first. The rash starts on the face and behind the ears before spreading, and the spots are "sometimes raised and join together to form blotchy patches. They're not usually itchy." The NHS advises asking for an urgent GP appointment or calling 111, and phoning the surgery before going in.

Rashes that itch but are not infections

Heat rash

Small raised spots 2mm to 4mm across, with an itchy, prickly feeling and mild swelling. It "looks red on white skin. It may be harder to see or look grey or white on brown or black skin." The NHS's treatment is entirely about temperature: loose cotton clothing, lightweight bedding, cool baths, a cold damp cloth or wrapped ice pack for up to 20 minutes, and tapping rather than scratching. It cannot be passed on.

Eczema

The NHS's description is compact: "skin that's itchy, dry and cracked may be atopic eczema. It's common behind the knees, elbows and neck, but it can appear anywhere." It advises speaking to a GP. Eczema is a long-term condition managed with emollients and, when flaring, prescribed treatment, rather than something that clears in a week.

Hives

"Raised, itchy patches or spots could be caused by an allergic reaction (hives)." Hives can usually be treated at home, but the NHS gives one hard exception: "call 999 if there's swelling around your child's mouth or they're struggling to breathe." A pharmacist can advise on antihistamines suitable for a toddler.

The others you will meet at nursery age

The NHS's rash guide also covers ringworm, impetigo, scabies and molluscum contagiosum, all of which turn up in group settings. It also covers rashes without fever or itching, including milia, erythema toxicum, nappy rash, baby acne and cradle cap — those last few belong to the first months rather than the toddler years, but they still appear in family photographs and cause panic.

A useful piece of the NHS advice on heat rash applies more widely: a pharmacist is the right first stop for most non-urgent rashes, and can tell you which treatments are suitable for a child's age. Hydrocortisone cream in particular is not for children under 10 without a doctor's advice.

What each one means for nursery

The HSE publishes the clearest exclusion rules, and they are less restrictive than most parents assume.

Chickenpox: keep them off "until all the spots have crusted over. This is usually about 5 to 7 days after the spots first appeared."
Hand, foot and mouth disease: "if your child has hand, foot and mouth disease but seems well enough to go to school, there's no need to keep them off. You do not need to wait until all the blisters have healed." Tell the setting.
Scarlet fever, measles, slapped cheek syndrome, impetigo: follow the advice from your GP.
High temperature: stay off until the temperature returns to normal and stays there without paracetamol or ibuprofen. The HSE's threshold is 38C (100.4F).
Head lice, cold sores, conjunctivitis, ringworm once treatment has started: no need to stay home, unless the child is generally unwell.

When to trust yourself

The NHS opens its rash guidance with a sentence worth taking seriously: "as a parent, you may know if your child seems seriously unwell and should trust your judgement." The glass test is a useful tool, not a permission slip — a child who looks very unwell needs help whether or not the rash blanches, and NICE's guidance is built around exactly that principle.

Common Toddler Rashes