Heat does not have to burn to leave a mark. If skin regularly exposed to a heater or hot water bottle becomes red or brown in a netlike pattern, do not assume it is simply dry.
What is this change?
Erythema ab igne is a reaction to repeated heat. Nearby heaters, heating pads and laptops resting on thighs are possible sources. Mild itching or stinging may occur; lack of pain does not rule out damage. Not every netlike mark is this condition: assessment includes examination and a heat-exposure history.
Three practical steps
- Stop repeatedly heating the affected area; cream alone will not address the cause.
- Put your laptop on a table and avoid direct contact between heaters and your body. A cover is not permission for prolonged exposure.
- If you use heat for ongoing pain, discuss its cause and other relief options with your clinician.
When should you seek care?
Persistent marks, pain, thickening or a non-healing sore need assessment. Have a growing lump checked promptly. Cancerous changes have rarely been reported in chronic cases, and a biopsy is sometimes needed.
Common questions
Will normal colour return?
It may gradually improve after heat exposure stops, but longstanding marks can persist. Recovery cannot be guaranteed.
Is this the same as heat rash?
No. Heat rash involves blocked sweat ducts, rather than this type of chronic heat exposure.
Do I need lightening cream or laser?
Identify the cause and stop damaging heat first. Treatment of remaining pigmentation should follow examination.
For non-urgent advice from Arvin: info@arvin.af. Note how long the marks have been present and the heat source involved. This educational article does not replace examination.