Dermatographia, also known as “skin writing,” refers to a condition where lightly scratched skin can turn into raised welts, forming hives. This is most often caused by an allergic reaction and is temporary, usually lasting around 30 minutes. However, the condition of dermographism can last for months or even years.
Approximately 2-5 percent of people have this condition, and it’s most common in older children and younger adults.