The word “dermatographia” comes from the Latin words for “skin” (dermato) and “writing” (graphia). It’s an apt nomenclature for a rare condition that causes an exaggerated allergic response to scratches, pressure, or irritations on the skin.
For approximately 2-5% of the population, the simple action of scratching an itch can have a cascade effect, sparking an outbreak of itchy, inflamed hives.
What Causes Dermatographia?
Despite sharing symptoms with other skin allergy responses, there is no specific allergen associated with dermatographia.
Researchers believe that the condition could be partially psychological, in that the act of scratching or rubbing “tricks” the brain into overreacting because it associates that action with past allergen contact.
To address the imagined problem, the body produces a chemical called histamine, just as it would in response to an actual allergen, which causes the inflammation and welts in the same pattern as the scratches.
What are the Symptoms of Dermatographia?
Patients living with dermatographia might notice any combination of the following symptoms after
- Hive-like, raised welts that develop in the same pattern as the scratching
- Itching, redness, and swelling
- Minor skin irritations that turn into deeper wounds
Typically, there is a slight delay of 5-7 minutes before these symptoms appear, and they last 15-30 minutes. In some cases, though, the welts can persist for several hours.
While the condition itself is not dangerous, it can be quite uncomfortable, especially for those with a prolonged response.
Diagnosis and Treatment
If you suspect that you might have dermatographia, the first step is scheduling an appointment with your dermatologist.
They will use a simple, in-office test to irritate the skin– usually applying pressure to the skin or by scratching or stroking the skin– then monitor whether you develop the tell-tale welts after a 10-minute waiting period.
Once diagnosis is confirmed, your dermatologist will recommend treatment options based on your anecdotal history with the condition.
Most people can manage their dermatographia symptoms with over-the-counter, non-drowsy antihistamines, such as:
- Loratadine (Claritin®)
- Cetirizine (Zyrtec®)
- Fexofenadine (Allegra®)
Reducing Dermatographia Triggers
Because dermatographia isn’t a serious condition, the best response is avoiding triggers that might prompt a histamine response.
It’s helpful to write down what you were doing before the hives developed, as well as taking assessment of your skin condition and environmental factors. These notes can help you and your dermatologist find your specific triggers.
- Dry skin
- Extreme hot or cold temperatures
- Itchy, ill-fitting, or synthetic fabric
- Feelings of anxiety or stress
- Lack of sleep
- Pre-existing skin conditions, including eczema
- Drinking alcohol