Treatment of Urticaria
Second-generation non-sedating H1 antihistamines are the first-line treatment for urticaria, with dose escalation up to four times the standard dose recommended for inadequate symptom control. 1, 2
First-Line Treatment
- Second-generation non-sedating H1 antihistamines are the mainstay of therapy for both acute and chronic urticaria 3, 1
- Options include cetirizine, desloratadine, fexofenadine, levocetirizine, loratadine, and mizolastine 1
- Patients should be offered at least two different non-sedating antihistamines, as responses and tolerance vary between individuals 3, 1
- Antihistamines should be used on a regular basis, not only after hives occur 4
Dose Escalation for Inadequate Response
- For inadequate symptom control, increasing the dose up to 4 times the standard dose is recommended when potential benefits outweigh risks 1, 5
- This approach has become common practice despite being above the manufacturer's licensed recommendation 3
- First-generation antihistamines may be added at night for additional symptom control 3
Second-Line Treatment
- Omalizumab (anti-IgE monoclonal antibody) is recommended for chronic spontaneous urticaria unresponsive to high-dose antihistamines 1, 2
- The standard starting dose is 300 mg every 4 weeks 1
- Allow up to 6 months for patients to respond to omalizumab before considering alternative treatments 1, 5
Third-Line Treatment
- Cyclosporine is recommended for patients who do not respond to high-dose antihistamines and omalizumab 1, 2
- It is effective in about two-thirds of patients with severe autoimmune urticaria at 4 mg/kg daily for up to 2 months 1
- Regular monitoring of blood pressure and renal function is required due to potential side effects 1, 2
Corticosteroids
- Oral corticosteroids should be restricted to short courses for severe acute urticaria or angioedema affecting the mouth 3
- Most patients respond to doses equivalent to 40 mg of prednisone daily 4
- Brief courses of steroids (3-10 days) can be employed for severe exacerbations, but should be an infrequent occurrence 5
- The addition of corticosteroids to antihistamines for acute urticaria remains controversial and requires further investigation 6
Special Considerations
Angioedema
- For hereditary angioedema, C1 inhibitor concentrate should be given for emergency treatment of serious attacks or as prophylaxis before surgery 3
- Anabolic steroids are the treatment of choice for maintenance therapy in most adults with hereditary angioedema 3
General Measures
- Identify and minimize aggravating factors such as overheating, stress, alcohol, and certain medications (aspirin, NSAIDs, codeine) 3, 2
- NSAIDs should be avoided in aspirin-sensitive patients with urticaria 3
- ACE inhibitors should be avoided in patients with angioedema without wheals 3, 2
- Cooling antipruritic lotions (calamine or 1% menthol in aqueous cream) can provide symptomatic relief 3
Special Populations
- In renal impairment: Avoid acrivastine in moderate renal impairment; halve the dose of cetirizine, levocetirizine, and hydroxyzine 1
- In hepatic impairment: Avoid mizolastine in significant hepatic impairment 1
- In pregnancy: Avoid antihistamines if possible, especially during the first trimester; choose chlorphenamine if necessary due to its long safety record 1
Treatment Algorithm
- Start with standard dose of second-generation H1 antihistamine 1, 7
- If inadequate control, increase dose up to 4 times the standard dose 1, 5
- If still inadequate control, add omalizumab 1, 2
- If inadequate response to omalizumab within 6 months, consider cyclosporine 1, 2
- For severe acute exacerbations, consider short courses of systemic corticosteroids 3, 5
Prognosis
- About 50% of patients with chronic urticaria presenting with wheals alone will be clear by 6 months 3
- Patients with wheals and angioedema have a poorer outlook, with over 50% still having active disease after 5 years 3
- More than half of patients with chronic urticaria will have resolution or improvement of symptoms within a year 8