When should you worry about a child's rash?
Last updated September 3, 2026.
The emergency sign: a rash like small bruises or bleeding under the skin that does not fade when you press a clear glass against it - the meningitis pattern; call an ambulance immediately. On brown or black skin, check palms, soles, lips, and inside the eyelids. Also emergency: rash with lip, mouth, or tongue swelling, tight throat, or breathing difficulty (anaphylaxis). Same-day: any rash plus fever with a genuinely unwell child (drowsy, floppy, not drinking), rash in a baby under 3 months with 38C or more, or a painful, blistering, fast-spreading rash. The reassuring majority: a child who is playing, drinking, and acting normal, with spots that fade under glass, can be watched for a day or two. Pymander is a free AI doctor, 24/7 by text, and can help you judge a rash tonight.
What to do
- Do the glass test: press a clear glass on the rash - non-fading means ambulance.
- Judge the child, not just the spots: drowsy, floppy, or not drinking escalates any rash.
- Swelling plus rash is anaphylaxis: lips, tongue, throat, breathing.
- Know the well-child rule: playing and drinking normally buys safe watching time.
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