The Glass Test: Checking Your Child's Rash

Key Information

• A Crucial Skill: Finding a rash on your child is worrying, but the "Glass Test" is a simple, life-saving skill that helps you determine if the rash requires urgent medical attention.
• How to Do It: Find a clear, solid glass. Press the side of the glass firmly against the spots or rash. You need to be able to see the skin clearly through the glass.
• The Reassuring Sign (Blanching): If the spots fade or disappear completely under the pressure, this is called a "blanching" rash. This is usually a sign of a common viral illness.
• The Danger Sign (Non-Blanching): If the spots do not fade and you can still see them clearly through the glass, this is a "non-blanching" rash. This indicates bleeding under the skin and is a potential sign of serious illness like meningitis or sepsis.

What to Do Next

If the rash does NOT fade (Non-Blanching):

This is a medical emergency. Do not wait. You must call 999 or go to your nearest A&E department immediately.

If the rash DOES fade (Blanching):

This is usually reassuring. However, keep a close eye on your child. If they seem unwell in themselves or you are concerned, please contact us for advice.

Further Information

For a complete list of meningitis symptoms (remember, do not wait for a rash to appear if your child is very unwell), please visit the NHS website.

Last reviewed: 22 December 2025
Next review due: 22 December 2028