Dermatographia (also known as “dermatographia”) is a condition in which lightly scratching your skin causes raised, red lines where you’ve scratched. It is not serious, but can be uncomfortable. In dermatographia, your skin cells are overly sensitive to minor injury, such as scratching. Signs and symptoms of dermatographia include redness, itching and swelling, similar to hives.
In most cases, dermatographia symptoms go away in a short time and you don’t need treatment. However, if symptoms are severe or bothersome there are medications which we can prescribe. Some simple self-care measures can also help you manage this skin condition.
Simple things can trigger symptoms of dermatographia. For example, rubbing from your clothes or bed sheets may irritate your skin. Cold, heat, pressure, exercise, sunlight and emotion can also trigger dermatographia.
You may notice symptoms of dermatographia within a few minutes of your skin being rubbed or scratched. The symptoms may last 30 minutes to a couple of hours, but typically fade within 15 minutes. Dermatographia rarely develops slowly and lasts several hours to several days and causes burning and pain.
The exact cause of dermatographia isn’t clear. It may be caused by an allergic response, yet no specific allergen has been identified.
- Other skin conditions. 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.
- Allergies. If you have a history of allergies, you may be more prone to developing dermatographia. The same immune system response that causes other allergies may also cause dermatographia.
- Heredity. As with other allergies, dermatographia may run in families.
Dermographia can occur at any age, but it tends to be more common in young adults in their 20s and 30s.
Signs and symptoms of dermatographia include redness, itching and swelling, similar to hives.
Tests and Diagnosis
Your dermatologist can diagnose dermatographia with a simple test. He or she will draw a tongue depressor across the skin of your arm or back. If a red swollen line or a welt (wheal) appears within a few minutes, you may have dermatographia.
To help find out what’s causing your dermatographia, we may ask you to keep a detailed diary of exposure to possible allergens over a period of two weeks to a month and a record of when dermatographia signs occur. We may also occasionally recommend allergy testing.
Because dermatographia may be triggered by many different things and because it can be aggravated by stress and other emotions, it is often difficult, even impossible, to determine the cause. In many people, the condition gets better over time, although it can be unpredictable.