Dermatographia 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. These marks usually disappear within 30 minutes.
The cause of dermatographia is unknown, but it can be triggered in some people by infections, emotional upset or medications such as penicillin.
Most people who have dermatographia don't seek treatment. If your signs and symptoms are especially bothersome, your doctor may recommend allergy medications such as cetirizine (Zyrtec) or diphenhydramine (Benadryl).
Signs and symptoms of dermatographia may include:
- Raised red lines
- Swelling
- Inflammation
- Hive-like welts
- Itching
The signs and symptoms may occur within a few minutes of your skin being rubbed or scratched and usually disappear within 30 minutes. Rarely, dermatographia develops more slowly and lasts several hours to several days.
The condition itself can last for months or years.
The exact cause of dermatographia isn't clear. It may be caused by an allergic response, yet no specific allergen has been identified.
Simple things can trigger symptoms of dermatographia. For example, rubbing from your clothes or bedsheets may irritate your skin. Sometimes, dermatographia is preceded by an infection, emotional upset or medications, such as penicillin.
Dermatographia can occur at any age, but it tends to be more common in teenagers and young adults. If you have other skin conditions, such as dry skin or dermatitis, you may be more susceptible to dermatographia. Any skin condition that causes a frequent urge to scratch may increase your risk.