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Do the glass test first:

  1. 1Press a clear glass firmly against the rash
  2. 2Look through the glass while pressing
  3. 3If the rash FADES (disappears) under pressure — that is usually reassuring
  4. !If the rash does NOT fade — call 911 immediately (possible meningitis)

Assess the rash

Answer these questions to determine what to do.

When to Seek Immediate Care

Call 911 or go to the ER if you see any of these signs

  • Does NOT fade when pressed (petechiae/purpura)
  • Hives with breathing difficulty or face/throat swelling
  • Rapidly spreading with high fever
  • Blistering rash with fever and mouth sores
  • Rash after a tick bite with bullseye pattern
  • Stiff neck, confusion, or severe headache with rash

Usually Not Serious

These signs suggest a common, non-dangerous rash

  • Fades when pressed (blanching)
  • Appeared after a fever broke (viral rash)
  • In a pattern matching contact (diaper area, necklace line)
  • Child is acting well despite the rash
  • Itchy but not spreading rapidly

Frequently Asked Questions

How do I do the glass test?

Press a clear drinking glass firmly against the rash and look through it. If the rash fades (disappears) when pressed, it is likely a common rash. If it does NOT fade - the spots stay visible through the glass - this could be a sign of meningitis or a bleeding disorder, and you should call 911.

My child has a rash after a fever broke - should I worry?

No, this is very common. Many viral illnesses cause a rash that appears AFTER the fever breaks. This is actually a good sign - it means the illness is resolving. The rash usually fades within a few days.

Can I give Benadryl for a rash?

Benadryl (diphenhydramine) is safe for most children over 2 and effective for itchy rashes and hives. Follow age-appropriate dosing on the package. It may cause drowsiness. If the rash involves breathing difficulty or face/throat swelling, this is an emergency - use an EpiPen if available and call 911.

What is the difference between hives and a viral rash?

Hives are raised, itchy welts that can appear and disappear quickly (within hours). They are usually an allergic reaction. Viral rashes are typically flat red spots that appear during or after an illness and stay in place for days. Both usually fade when pressed.

This guide is for quick reference and does not replace professional medical advice. When in doubt, call your pediatrician or go to the ER.