What is the initial treatment for severe urticaria in an adult?

Initial Treatment for Severe Urticaria in Adults

For severe acute urticaria in adults, start with a second-generation non-sedating H1 antihistamine at standard dose, and add a short course of oral prednisolone 50 mg daily for 3 days if antihistamines alone do not provide adequate control. 1, 2

First-Line: High-Dose Antihistamines

• Begin with a second-generation non-sedating H1 antihistamine (cetirizine, desloratadine, fexofenadine, levocetirizine, loratadine, or mizolastine) at standard dose 3, 2
• If symptoms remain inadequately controlled after 2-4 weeks, increase the dose up to 4 times the standard dose 3, 2
• Offer at least two different non-sedating antihistamines to each patient, as individual responses and tolerance vary significantly between agents 3, 2
• First-generation antihistamines like hydroxyzine may be added at night for additional symptom control and to help patients sleep, though they should not be used as first-line monotherapy due to sedating properties 2

Add Short-Course Corticosteroids for Severe Cases

• For severe acute urticaria not responding adequately to antihistamines, add prednisolone 50 mg daily for 3 days 1
• Lower doses are frequently effective and should be considered to minimize corticosteroid exposure 1
• Alternative dosing: prednisone 0.5-1 mg/kg/day until hives resolve, or 40 mg daily equivalent 1, 4
• Short courses of 3-10 days are appropriate for severe acute exacerbations 1, 5

Critical Pitfall to Avoid

• Do NOT use long-term oral corticosteroids in chronic urticaria except in very selected cases under regular specialist supervision 1, 2
• This is a firm contraindication due to cumulative toxicity and poor risk-benefit ratio 1
• Recent systematic review evidence shows that adding corticosteroids to antihistamines did not improve symptoms of acute urticaria compared to antihistamine alone in two out of three randomized controlled trials 6

If Antihistamines and Short-Course Steroids Fail

For chronic spontaneous urticaria (symptoms persisting >6 weeks) that is refractory to high-dose antihistamines:

• Second-line: Add omalizumab 300 mg subcutaneously every 4 weeks 3, 2, 5

• Allow up to 6 months for patients to respond before considering treatment failure 3, 2

• Omalizumab is effective in approximately 70% of antihistamine-refractory patients 5, 7

• Third-line: Add cyclosporine 4 mg/kg daily (up to 5 mg/kg) for up to 2 months if omalizumab fails 8, 3, 2

• Cyclosporine is effective in approximately 65-70% of patients with severe urticaria unresponsive to antihistamines 8, 5

• Monitor blood pressure and renal function every 6 weeks due to potential nephrotoxicity and hypertension 3, 2

• Treatment duration of 16 weeks is superior to 8 weeks for reducing therapeutic failures 3

Adjunctive Measures

• Identify and minimize aggravating factors including overheating, stress, alcohol, aspirin, NSAIDs, and codeine 3, 2
• Cooling antipruritic lotions (calamine or 1% menthol in aqueous cream) can provide symptomatic relief 3
• Avoid NSAIDs in aspirin-sensitive patients and ACE inhibitors in patients with angioedema without wheals 2

Emergency Management

• For severe urticaria with anaphylaxis or angioedema affecting the airway, administer intramuscular epinephrine 0.5 mL of 1:1000 (500 µg) immediately 8, 9
• Fixed-dose epinephrine pens (300 µg for adults) should be prescribed for patients at risk of life-threatening attacks 8