The Human Etch-A-Sketch: A "Skin Writer" Opens Up About Her Skin Condition
Sarah Beal can draw on her hand using the end of a spoon and then watch it disappear only minutes later.
She has a skin condition called dermatographia which means that the slightest scratch can cause her skin to swell.
"My skin is so sensitive that sometimes even clothes can feel uncomfortable," explained Beal. "I can scratch my arm or my back and long lines will come up."
Dermatographia is thought to be caused when the cells under the surface of the skin release histamines under the slightest pressure. This causes the skin to swell and triggers a type of allergic reaction.
"I grabbed a spoon and with the handle I drew a heart on my arm. When I saw it appear I loved it. I quickly took a picture of the heart and uploaded it to Facebook before it disappeared," she added.
Another woman used her condition to create art a while ago: