What Is Dermatographia (Skin Writing)? Risk Factors, Pictures, Treatment, and More

Have you ever scratched your arm or leg and looked down a few minutes later to find a raised red or discolored mark where you scratched? If you've experienced this phenomenon, you may have dermatographia.

People with dermatographia develop raised marks or even hives (welts) when pressure - like firm touch or scratching - is applied to their skin.

Dermatographia is also called:

• Dermographism

• Urticaria factitia

• Dermographic urticaria

• Skin writing

For some people, dermatographia doesn't bother them too much. Some people even turn it into an art form. But other people who experience dermatographia suffer from intense itching and even have trouble wearing certain types of clothing.

If you think you have dermatographia, here's everything you need to know about what causes it, how it's diagnosed, and how you can treat it.

Dermatographia symptoms

Dermatographia symptoms can range from one person to the next. The symptoms are usually on the skin, but they can also involve areas like the lips and vulva. Symptoms include:

• Raised lines where you scratched that can be red, pink, purple, white, or skin-colored

• Itching

• Swelling

• Hives or welts

• Pink, red, or brown discolored patches around the red areas

What does dermatographia look like?

Here are some pictures of dermatographia to help you know what it looks like.

What causes dermatographia?

Dermatographism is a kind of allergic reaction. When someone with this condition applies pressure to their skin, their mast cells release a chemical called "histamine" along with other inflammatory substances.

These substances cause skin discoloration and swelling - better known as hives. But unlike other allergic reactions, these hives don't only look like oval welts. They take the shape of any pressure applied to your skin.

The hives appear within 5 to 7 minutes and fade over 15 to 30 minutes. They may be itchy and usually form on your arms, legs, or torso.

Researchers aren't sure why certain people's bodies release histamine in response to skin pressure, while others' don't. Dermatographia has been associated with different triggers, including:

• Excessively dry skin

• Exercise

• Strong emotions or stress

• Cold or hot temperatures

• Infections caused by viruses, bacteria, or fungi

• Certain medications, like penicillin

• COVID-19 vaccines

Who's most at risk of dermatographia?

Up to 5% of people experience dermatographia at some point in their lives. It's more common in younger people, especially children.

People with certain medical conditions are more likely to develop dermatographism, including those with:

• Thyroid conditions

• Diabetes

• Reactive polyarthritis

• Behçet's disease

• Atopic dermatitis

People who're pregnant or going through menopause are also more likely to experience dermatographia. And the condition can also run in families.

How is dermatographia diagnosed?

A healthcare professional can diagnose dermatographia by talking to you about your symptoms and doing a provocation test.

During a provocation test, they'll stroke the skin on your forearm or back with the blunt end of a pencil or with a special instrument for dermatographia testing. After that, you'll wait about 10 minutes to see if raised marks show up along the path of the object. If they do, it's very likely that you experience dermatographia.

Make sure you don't take any antihistamines for several days before your provocation test, because they can affect how your body responds to the test.

How do you treat dermatographia?

In most situations, treatment for dermatographia isn't needed because it doesn't cause symptoms or symptoms go away on their own. For some people, dermatographia causes itching that can interfere with their daily lives. This itching can keep them from sleeping, working, wearing certain fabrics, and even going out in certain types of weather.

Luckily, there are different treatments that can help manage symptoms and keep the welts from forming.

Medications and therapies

Over-the-counter (OTC) antihistamines can treat dermatographia. Sometimes, higher than standard doses are needed, so it's important to talk to your healthcare team before using them. OTC options include:

• Loratadine (Claritin)

• Cetirizine (Zyrtec)

• Diphenhydramine (Benadryl)

• Fexofenadine (Allegra)

For more severe cases, you may need:

• Prescription-strength antihistamines, like hydroxyzine (Vistaril)

• Another type of histamine blocker, called "H2 blockers"

Other treatment options include UV light therapy and omalizumab (a type of monoclonal antibody).

How can I prevent dermatographia?

When it comes to dermatographia, prevention may be the best treatment. For this to work, you need to know what usually triggers your symptoms. Keeping a journal may help you pinpoint your specific triggers.

Common triggers to avoid

Everyone is different, but here are some common dermatographia triggers:

• Dry skin: Dry skin is a common trigger for many people. To avoid dry skin, focus on skin hydration by using non-drying soaps, detergents, and other skin care products. You can also use non-irritating emollients to keep your skin hydrated.

• Trauma: Avoid causing direct trauma to your skin, like scratching or rubbing. Choose looser fitting clothing, including undergarments, whenever possible.

• Temperature: If temperature is one of your triggers, try to avoid spending time in the heat or cold when possible. For example, turn down the temperature in your baths and showers.

• Fabrics: Certain fabrics can trigger dermatographia, like scratchy wool or synthetic fibers. Fabrics like cotton and linen might be less irritating.

• Diet: Some people notice improvements in their symptoms when they eat a healthier diet that's rich in anti-inflammatory foods.

• Stress: Mental health plays an important role in managing your triggers. Make sure you're getting enough sleep, exercise, and mental health support.

Frequently asked questions

Images used with permission from VisualDx (www.visualdx.com).