PAEDIATRICS
Rashes in Children: Common Causes and When to Be Seen
Why rashes can be difficult to interpret, what matters more than the label alone, and when examination is needed.
Rashes are one of the most common reasons parents seek medical advice — and one of the most difficult to interpret without examination. They range from mild viral rashes that resolve without treatment to signs of bacterial infection, allergic reaction, or occasionally something more serious. What the rash looks like, where it is spreading, whether it is accompanied by fever, how the child is behaving, and whether it blanches under pressure all influence the clinical assessment.
Examination is important because rashes often look different in photographs than in person, and the clinical context — fever, the child’s overall state, recent illness, medication — is essential for interpretation.
ON THIS PAGE
Common rash types in children
Viral exanthems are among the most common childhood rashes. They typically appear as widespread, blotchy, pink or red patches during or after a viral illness. They usually blanch when pressed, are not particularly itchy, and resolve over a few days without specific treatment.
Eczema flare-ups produce dry, itchy, red or inflamed patches, commonly in the creases of elbows, behind the knees, and on the face in younger children. Urticaria (hives) presents as raised, itchy welts that can appear suddenly, often in response to an allergen, infection, or sometimes without a clear trigger. Impetigo is a bacterial skin infection that causes golden-crusted, weeping sores — typically around the nose and mouth — and usually requires antibiotic treatment.
Red flag
The glass test and when it matters
A non-blanching rash — one that does not fade when pressed with a clear glass — is a red flag that requires urgent medical assessment. This type of rash can be a sign of meningococcal disease or other serious infections. It typically appears as small dark red or purple spots (petechiae) or larger bruise-like patches that do not disappear under pressure. If you see a non-blanching rash in a child who is unwell, do not wait for a GP appointment — seek emergency medical assessment through A&E or call 999.
Same-day appointments available. Book online or call 020 7736 7557.
When a GP appointment is the right step
A paediatric GP appointment is appropriate when the rash is new and you are unsure what it is, when it is spreading or changing, when it is accompanied by fever that does not settle, when it looks infected (increasing redness, warmth, swelling, discharge), when the child is itching intensely or seems uncomfortable, when a rash keeps returning, or when over-the-counter treatments have not helped. Examination allows the GP to assess the rash directly, consider the wider clinical picture, and decide whether treatment, monitoring, or onward referral is appropriate.
In-person assessment
Why examination matters more than a photo
Rashes are one area where in-person examination is genuinely more useful than a photograph or video. A GP can assess texture, warmth, distribution, whether the rash blanches, and how the child looks overall — none of which translate reliably through a screen. Basuto keeps same-day appointments available for children with new or concerning rashes.
Common questions
What is the glass test, and when does it indicate an emergency?
A non-blanching rash — one that does not fade when pressed with a clear glass — is a red flag requiring urgent medical assessment. It can indicate meningococcal disease or other serious infections. If you see a non-blanching rash in a child who is unwell, do not wait for a GP appointment — seek emergency assessment through A&E or call 999.
Which common childhood rashes are usually harmless?
Viral exanthems — widespread, blotchy, pink or red patches that blanch when pressed and appear during or after a viral illness — usually resolve over a few days without specific treatment. Eczema flare-ups, mild urticaria, and some heat-related rashes are also common and often self-limiting. But context matters: rashes accompanied by fever, changes, or an unwell child need clinical review.
Why is in-person examination usually better than sending a photo?
Rashes often look different in photographs than in person. A GP assesses texture, warmth, distribution, whether the rash blanches, and how the child looks overall — none of which translate reliably through a screen. For a new or concerning rash, in-person review is significantly more useful. Same-day appointments are kept available for these situations.
FURTHER READING