What is the approach to managing hives in a young adult?

Approach to Hives in a Young Adult

Start with a second-generation non-sedating H1 antihistamine (cetirizine, desloratadine, fexofenadine, levocetirizine, loratadine, or mizolastine) at standard dosing, and if symptoms persist after 2-4 weeks, increase the dose up to 4 times the standard dose before considering additional therapies. 1, 2

Initial Assessment and Classification

Determine whether the urticaria is acute (lasting less than 6 weeks) or chronic (lasting 6 weeks or more), as this guides both workup and treatment expectations. 3, 4

Key clinical features to document:

• Duration and frequency of wheals (individual lesions should resolve within 24 hours) 4
• Presence of angioedema (occurs in conjunction with wheals in many cases) 4, 5
• Timing and pattern of symptoms (spontaneous vs. triggered by specific stimuli like heat, cold, pressure, or exercise) 6, 5
• Associated symptoms suggesting anaphylaxis (respiratory symptoms, throat swelling, hypotension) that would require immediate epinephrine 7

First-Line Treatment: Second-Generation Antihistamines

Offer the patient a choice of at least two different non-sedating antihistamines, as individual responses and tolerance vary significantly. 1, 2 Options include:

• Cetirizine (has shortest time to maximum concentration, advantageous for rapid relief) 6
• Desloratadine
• Fexofenadine
• Levocetirizine
• Loratadine
• Mizolastine 1, 2

These agents are equally effective as first-generation antihistamines like hydroxyzine but without the problematic CNS sedation and anticholinergic effects. 8

Dose escalation strategy:

• Start at standard dosing
• If inadequate symptom control after 2-4 weeks, increase up to 4 times the standard dose when benefits outweigh risks 1, 2, 6
• First-generation antihistamines (like hydroxyzine) may be added at night for additional symptom control and to aid sleep, but avoid as monotherapy due to sedating effects 2

Second-Line Treatment: Omalizumab

For chronic spontaneous urticaria unresponsive to high-dose antihistamines, add omalizumab 300 mg subcutaneously every 4 weeks. 1, 2, 9 This is FDA-approved for patients 12 years and older with chronic spontaneous urticaria who remain symptomatic despite H1 antihistamine treatment. 9

Critical omalizumab considerations:

• Dosing in chronic spontaneous urticaria is fixed at 150 mg or 300 mg every 4 weeks and does NOT depend on IgE level or body weight (unlike in asthma) 9
• Can increase to 600 mg every 2 weeks in patients with insufficient response 1, 2
• Allow up to 6 months for response before declaring treatment failure 1, 2
• At least 30% of patients have insufficient response to omalizumab, particularly those with IgG-mediated autoimmune urticaria 3
• Must be initiated in a healthcare setting due to risk of anaphylaxis, which can occur after first dose or even beyond 1 year of treatment 9

Third-Line Treatment: Cyclosporine

For patients who fail high-dose antihistamines and omalizumab within 6 months, add cyclosporine at 4-5 mg/kg daily for up to 2 months. 1, 2, 6

Cyclosporine is effective in approximately 54-73% of patients, particularly those with autoimmune chronic spontaneous urticaria who don't respond to omalizumab. 1, 3, 10

Mandatory monitoring requirements:

• Blood pressure and renal function every 6 weeks due to risk of kidney dysfunction and hypertension 1, 2, 6, 3

Adjunctive Measures and Trigger Avoidance

Identify and minimize aggravating factors:

• Overheating, stress, and alcohol 1, 2, 6
• NSAIDs and aspirin (avoid in aspirin-sensitive patients with urticaria) 1, 2, 6
• ACE inhibitors (avoid in patients with angioedema without wheals) 1, 2
• Codeine 1, 2

Symptomatic relief:

• Cooling antipruritic lotions (calamine or 1% menthol in aqueous cream) can provide additional relief 1, 6

Role of Corticosteroids

Restrict oral corticosteroids to short courses (3-10 days) for severe acute exacerbations only; do not use chronically due to cumulative toxicity. 2, 6 Their benefit is limited to preventing late-onset biphasic reactions, not immediate symptom relief. 7

Limited Laboratory Workup

For chronic urticaria, only pursue limited nonspecific laboratory testing unless history or physical examination suggests specific underlying conditions. 10 Chronic urticaria is idiopathic in 80-90% of cases. 10 Approximately 50% of cases involve mast cell-activating IgE and/or IgG autoantibodies. 3

Prognosis and Patient Education

Counsel patients that approximately 50% with chronic urticaria presenting with wheals alone will be clear by 6 months, though those with both wheals and angioedema have a poorer outlook with over 50% still having active disease after 5 years. 2 More than half of patients with chronic urticaria will have resolution or improvement within one year. 10

Special Population Adjustments

Renal impairment:

• Avoid acrivastine in moderate renal impairment
• Halve the dose of cetirizine, levocetirizine, and hydroxyzine in moderate renal impairment
• Avoid cetirizine and levocetirizine in severe renal impairment 1, 2

Hepatic impairment:

• Avoid mizolastine in significant hepatic impairment
• Avoid hydroxyzine in severe liver disease 1, 2

Pregnancy:

• Avoid antihistamines if possible, especially during first trimester
• If necessary, choose chlorphenamine due to long safety record
• Loratadine and cetirizine are FDA Pregnancy Category B 1, 2