This information is provided by the National Institutes of Health (NIH) Genetic and Rare Diseases Information Center (GARD).
Familial dermographism is a condition also known as skin writing. When people who have dermatographia lightly scratch their skin, the scratches redden into a raised wheal similar to hives. Signs and symptoms of dermatographia include raised red lines, swelling, inflammation, hive-like welts and itching. Symptoms usually disappear within 30 minutes. The exact cause of this condition is unknown. Treatment may invovle use of antihistamines if symptoms do not go away on their own.
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