9 doctors weighed in:
What causes the red mark on your skin after you sit in one position for too long?
9 doctors weighed in

Dr. Mark Taylor
Dermatology
6 doctors agree
In brief: Vessel flushing
The blood pushed out of the vessels by the pressure of sitting and a relative hypoxia occurs.
When the pressure is relieve the hypoxia dilates the vessels causing a flush of blood into the vessel making a red mark.

In brief: Vessel flushing
The blood pushed out of the vessels by the pressure of sitting and a relative hypoxia occurs.
When the pressure is relieve the hypoxia dilates the vessels causing a flush of blood into the vessel making a red mark.
Dr. Mark Taylor
Dr. Mark Taylor
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Dr. Otto Placik
Surgery - Plastics
2 doctors agree
In brief: Series of events:CO2
It is a series of biological processes.
Initially the pressure compresses blood vessels & occludes them, blocking the circulation to area & depriving the local cells of oxygen. When the pressure is relieved, the "suffocated" or ischemic cells in the area build up co2 and other humoral factors which make the local blood vessels dilate and open up (causing the red appearance) to deliver oxygen!

In brief: Series of events:CO2
It is a series of biological processes.
Initially the pressure compresses blood vessels & occludes them, blocking the circulation to area & depriving the local cells of oxygen. When the pressure is relieved, the "suffocated" or ischemic cells in the area build up co2 and other humoral factors which make the local blood vessels dilate and open up (causing the red appearance) to deliver oxygen!
Dr. Otto Placik
Dr. Otto Placik
Thank
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