Treatment for Hives (Acute Urticaria)
Start with a second-generation non-sedating H1 antihistamine (cetirizine, desloratadine, fexofenadine, levocetirizine, loratadine, or mizolastine) at standard dosing as first-line treatment for acute urticaria. 1, 2, 3
First-Line Treatment Approach
Second-generation non-sedating H1 antihistamines are the definitive first-line treatment for acute urticaria, with cetirizine, desloratadine, fexofenadine, levocetirizine, loratadine, and mizolastine as preferred options 1, 2, 3
Offer at least two different non-sedating antihistamines to trial, as individual responses and tolerance vary significantly between patients 1, 2, 3
Cetirizine reaches maximum concentration fastest (shortest time to peak), making it the most advantageous choice when rapid symptom relief is needed for acute symptoms 1, 2
These second-generation agents are equally effective as first-generation antihistamines like hydroxyzine but without the problematic CNS sedation and anticholinergic side effects 4, 5
Dose Escalation Strategy
If symptoms persist after 2-4 weeks on standard dosing, increase the dose up to 4 times the standard dose before adding other therapies 1, 2, 3
This dose escalation strategy should be attempted before moving to second-line treatments 2, 6
Critical Pitfall: Corticosteroids in Acute Urticaria
Oral corticosteroids should be restricted to short courses (3-10 days) for severe acute urticaria or angioedema only—never for chronic management. 2, 3
Recent evidence shows that adding corticosteroids (prednisone) to antihistamines did not improve symptoms of acute urticaria compared to antihistamine alone in two out of three RCTs 7
Corticosteroids have slow onset of action, work by inhibiting gene expression, and are ineffective for acute symptom relief 2
Chronic use leads to cumulative toxicity that outweighs any benefit 1, 2
Trigger Identification and Avoidance
Identify and minimize aggravating factors including overheating, stress, alcohol, aspirin, NSAIDs, and codeine 1, 2, 3
Avoid NSAIDs in aspirin-sensitive patients with urticaria 2, 3
Avoid ACE inhibitors in patients with angioedema without wheals 2, 3
Emergency Situations: When NOT to Use Antihistamines
Never use antihistamines or corticosteroids in place of epinephrine for anaphylaxis. 2
Antihistamines take 30-120 minutes to reach peak plasma concentrations and lack the vasoconstrictive, bronchodilatory, and mast cell stabilization properties of epinephrine 2
For severe urticaria with anaphylaxis or angioedema affecting the airway, administer intramuscular epinephrine 0.5 mL of 1:1000 (500 µg) immediately 3
Special Population Adjustments
Renal Impairment
- Avoid acrivastine in moderate renal impairment 2, 3
- Halve the dose of cetirizine, levocetirizine, and hydroxyzine in moderate renal impairment 2, 3
Hepatic Impairment
- Avoid mizolastine in significant hepatic impairment 2, 3
- Avoid hydroxyzine in severe liver disease 2, 3
Pregnancy
- Avoid antihistamines if possible, especially during the first trimester 2, 3
- If necessary, choose chlorphenamine due to its long safety record 2, 3
Adjunctive Symptomatic Measures
Cooling antipruritic lotions (calamine or 1% menthol in aqueous cream) can provide symptomatic relief 1
First-generation antihistamines may be added at night for additional symptom control if needed, but their sedating effects should be considered 1, 3
Progression to Chronic Urticaria Management
If acute urticaria persists beyond 6 weeks (becoming chronic spontaneous urticaria) and remains unresponsive to high-dose antihistamines:
Add omalizumab 300 mg subcutaneously every 4 weeks as second-line treatment 1, 2, 3
Allow up to 6 months for response before considering treatment failure 1, 2, 3
For patients who fail omalizumab within 6 months, add cyclosporine at 4-5 mg/kg daily for up to 2 months with regular blood pressure and renal function monitoring 1, 2, 3