Dermatographia is typically diagnosed through a simple physical examination. A healthcare provider will gently scratch or stroke the patient’s skin with a blunt object (e.g., a tongue depressor) and observe any reaction. If raised welts appear within a few minutes, a diagnosis of dermatographia is likely.
Dermatographia has many different signs and causes can differ from person to person. What makes dermatographia hard to recognize is that symptoms don’t appear on their own usually. They are reactions to scratches, repeated rubbing, or heat. The first time this happens is usually without warning and without prior symptoms.
Itchy red skin is the most common and usually first sign of dermatographia. A part of the skin itches and the constant scratching causes an irritation and red welts and rashes appear along the skin. It can happen after you itch a part of your body, or even if clothing is too tight.
