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Diseases and Conditions
Special to CNN.com
Dermatographia is a condition in which lightly scratching your skin causes raised, red lines where you've scratched. It's not serious, but it can be uncomfortable. In dermatographia, the 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 don't require treatment. But, if signs and symptoms are severe or bothersome, your doctor may suggest taking antihistamines. Simple self-care measures also can help you manage this skin condition.
Signs and symptoms
Other than raised red lines, dermatographia often causes no other problems. In some people, however, scratching or rubbing the skin may cause uncomfortable irritation, including swelling, inflammation, hive-like welts and itching.
Simple things can trigger symptoms of dermatographia. For example, rubbing from your clothes or bedsheets may irritate your skin. Cold, heat, pressure, sunlight and emotion also can trigger dermatographia symptoms.
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 after the irritation to your skin ends. Rarely, dermatographia develops slowly and lasts several hours to several days and causes burning and pain.
Dermatographia affects up to 5 percent of the population and is the most common form of hives. The exact cause of dermatographia isn't clear. It may be caused by an allergic response, yet no specific allergen has been identified.
Factors that may increase your risk of dermatographia include:
Dermatographia can occur at any age, but it tends to be more common in young adults in their 20s and 30s.
When to seek medical advice
See your doctor if you have symptoms of dermatographia such as skin redness and swelling that recur frequently or don't go away on their own. If your symptoms are severe and very uncomfortable, you may need treatment.
Screening and diagnosis
Your doctor 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, your doctor 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 symptoms occur. Your doctor may also recommend skin testing for allergies.
Because dermatographia may be triggered by many different things and because it can be aggravated by stress and other emotions, it's sometimes difficult — or impossible — to determine the cause.
Dermatographia generally is harmless. It leaves no lasting marks and often causes only minor symptoms. However, dermatographia can be uncomfortable. If it's linked to allergies, finding what you are allergic to may help. If dermatographia is a bothersome problem for you, work closely with your doctor to manage it.
Signs and symptoms of dermatographia usually go away on their own and treatment generally isn't necessary. However, if they are severe or bothersome, your doctor may recommend antihistamine medications. These drugs block histamine, an inflammatory chemical released by your immune system during an allergic reaction. A low dose of antihistamine usually provides relief at the time of the reaction. You might need to take medication on a regular basis if your symptoms are severe.
Certain things can help you to reduce discomfort and relieve the symptoms of dermatographia. Try these tips:
June 15, 2006