What are the treatment options for dermatographic urticaria?

Treatment of Dermatographic Urticaria

Second-generation non-sedating H1 antihistamines are the first-line treatment for dermatographic urticaria (symptomatic dermographism), with doses that can be increased up to four times the standard dose if initial therapy provides inadequate control. 1, 2

First-Line Treatment: Non-Sedating Antihistamines

• Start with a second-generation H1 antihistamine at standard dosing, such as cetirizine 10 mg, loratadine 10 mg, fexofenadine 180 mg, desloratadine 5 mg, or levocetirizine 5 mg daily. 1, 3

• Cetirizine has the shortest time to maximum concentration, making it particularly advantageous when rapid symptom relief is needed for acute flares of dermographism. 1

• Offer at least two different non-sedating antihistamines before declaring treatment failure, as individual responses and tolerance vary significantly between patients. 1

• If standard dosing is inadequate after 2-4 weeks, increase the dose up to four times the standard dose (e.g., cetirizine 40 mg daily, fexofenadine 720 mg daily). 1, 2

• Avoid first-generation sedating antihistamines (diphenhydramine, hydroxyzine) as first-line therapy due to significant sedation and cognitive impairment without superior efficacy. 1

Adjunctive First-Line Measures

• Adding an H2 antihistamine (such as cimetidine) to an H1 antihistamine may provide better control in symptomatic dermographism, though evidence is limited. 1, 3

• Identify and minimize mechanical triggers including scratching, tight clothing, friction from belts or straps, and physical pressure on the skin. 1, 2

• Avoid aggravating factors such as overheating, hot showers, stress, alcohol, aspirin, NSAIDs, and codeine, which can lower the threshold for mast cell degranulation. 1

• Use emollients regularly to maintain skin barrier function and reduce dryness that may increase susceptibility to mechanical stimulation. 1

• Cooling antipruritic lotions (calamine or 1% menthol in aqueous cream) can provide symptomatic relief for itching. 1

Second-Line Treatment: Omalizumab

• For dermographism unresponsive to high-dose antihistamines, omalizumab (anti-IgE monoclonal antibody) is recommended at 300 mg subcutaneously every 4 weeks. 1, 2

• Allow up to 6 months for patients to respond to omalizumab before considering it a treatment failure and moving to alternative therapies. 1

Third-Line Treatment: Cyclosporine

• For patients who fail both high-dose antihistamines and omalizumab, cyclosporine at 4 mg/kg daily for up to 2 months is effective in approximately two-thirds of patients with severe autoimmune urticaria. 1

• Monitor blood pressure and renal function every 6 weeks during cyclosporine therapy due to potential nephrotoxicity and hypertension. 1

Role of Corticosteroids

• Systemic corticosteroids should never be used as maintenance therapy for chronic dermographism and should only be reserved for short courses (3-10 days) during severe acute flares. 1

• Avoid prolonged or repeated corticosteroid courses due to risks of adrenal suppression, dermal thinning, hypertension, diabetes, osteoporosis, and immunosuppression. 1

Topical Treatments

• Topical doxepin may be prescribed for localized symptomatic areas, but treatment should be limited to 8 days, applied to no more than 10% of body surface area, with a maximum of 12 g daily due to risk of allergic contact dermatitis. 4

• Topical clobetasone butyrate or menthol may provide modest benefit for localized pruritus. 4

• Do not use topical crotamiton cream or capsaicin for dermographism, as evidence does not support their efficacy. 4, 1

Important Caveats

• Dermographism is diagnosed by provocation testing: firmly stroking the skin with a tongue depressor or fingernail produces a linear wheal within 5-10 minutes. 2

• The pathophysiology involves mechanical stress-induced mast cell activation with histamine and pro-inflammatory mediator release, explaining why antihistamines are so effective. 2

• Approximately 50% of patients with wheals alone achieve remission by 6 months, though those with associated angioedema have a worse prognosis with over 50% still symptomatic after 5 years. 5

• NSAIDs should be strictly avoided in aspirin-sensitive patients with urticaria, as they can trigger severe exacerbations. 1