What is the recommended approach for outpatient management of urticaria?

Outpatient Management of Urticaria

The recommended first-line treatment for urticaria in the outpatient setting is second-generation H1-antihistamines at standard doses, with dose escalation up to four times the standard dose for inadequate response. 1, 2

Initial Assessment and Classification

• Distinguish between acute urticaria (≤6 weeks) and chronic urticaria (>6 weeks), as management approaches differ 3
• Identify if urticaria is spontaneous or inducible (triggered by specific stimuli like physical factors) 1, 3
• Evaluate for urticarial vasculitis if wheals last longer than 24 hours (requires skin biopsy) 1
• Check for associated angioedema, which may indicate a more persistent course 4, 3

First-Line Treatment

• Begin with second-generation (non-sedating) H1-antihistamines such as cetirizine, desloratadine, fexofenadine, levocetirizine, or loratadine 2, 5
• Use standard doses initially for 2-4 weeks to assess response 6, 2
• For inadequate response, increase antihistamine dose up to four times the standard dose 1, 5
• Consider offering at least two different non-sedating H1-antihistamines as responses vary between individuals 1

Second-Line and Adjunctive Treatments

• Add H2-antihistamines (such as ranitidine or famotidine) for resistant cases 2, 7
• Consider adding leukotriene receptor antagonists (montelukast) as adjunctive therapy, particularly for aspirin-sensitive and autoimmune urticaria 6
• Short courses of oral corticosteroids may be used for acute urticaria (e.g., prednisolone 50 mg daily for 3 days in adults) 6
• Avoid long-term oral corticosteroids in chronic urticaria except in very selected cases under specialist supervision 6

Management Based on Urticaria Type

Acute Urticaria

• Use second-generation H1-antihistamines as first-line therapy 5, 7
• Short courses of oral corticosteroids may help shorten duration 6, 7
• Identify and remove triggering agents when possible 2, 5

Chronic Spontaneous Urticaria

• Start with second-generation H1-antihistamines at standard doses 5, 8
• Increase dose up to four times if needed 1, 8
• For antihistamine-refractory cases, consider omalizumab (300mg subcutaneously every 4 weeks) 9, 8
• Cyclosporine (up to 5mg/kg body weight) can be considered for severe cases unresponsive to antihistamines and omalizumab 1, 8

Urticarial Vasculitis

• Requires confirmation by skin biopsy 1
• May need short tapering courses of oral steroids over 3–4 weeks 6, 1
• Consider immunomodulatory agents for severe cases 6, 1

Special Considerations

Pediatric Patients

• Second-generation H1-antihistamines are the cornerstone of management 2
• Dose and age restrictions vary for younger children; consult relevant data sheets before prescribing 6
• Avoid first-generation antihistamines due to sedative effects that can impact school performance 2

Pregnancy

• Avoid all antihistamines if possible, especially during the first trimester 6
• If treatment is necessary, chlorphenamine has the longest safety record in the UK 6
• Loratadine and cetirizine are FDA Pregnancy Category B drugs 6

Renal Impairment

• Avoid acrivastine in moderate renal impairment (creatinine clearance 10–20 mL/min) 6
• Halve the dose of cetirizine, levocetirizine, and hydroxyzine 6
• Avoid cetirizine, levocetirizine, and alimemazine in severe renal impairment 6
• Use loratadine and desloratadine with caution in severe renal impairment 6

Hepatic Impairment

• Avoid mizolastine in significant hepatic impairment 6
• Avoid alimemazine in hepatic impairment (hepatotoxic) 6
• Avoid chlorphenamine and hydroxyzine in severe liver disease due to inappropriate sedating effects 6

General Measures and Patient Education

• Minimize non-specific aggravating factors such as overheating, stress, and alcohol 1, 2
• Avoid drugs that can worsen urticaria, such as aspirin, NSAIDs, and codeine 1, 2
• Apply cooling antipruritic lotions (calamine or 1% menthol in aqueous cream) for symptomatic relief 1, 2
• Educate patients about the chronic nature of the condition and potential for eventual recovery 1

Treatment-Resistant Cases

• For severe antihistamine-resistant chronic urticaria, consider omalizumab 300mg every 4 weeks 1, 9
• Cyclosporine has been effective in about two-thirds of patients with severe autoimmune urticaria at 4 mg/kg daily 6
• Other options for refractory cases include tacrolimus, mycophenolate mofetil, plasmapheresis, and intravenous immunoglobulins 6

Monitoring and Follow-up

• Regularly assess disease activity, impact on quality of life, and treatment response 1
• For patients on cyclosporine, monitor blood pressure and renal function every 6 weeks 1
• Consider stepping down therapy after achieving complete control for at least 3 consecutive months 1