What is the treatment for acute urticaria?

Treatment of Acute Urticaria

For acute urticaria, second-generation non-sedating H1 antihistamines are the first-line treatment, with dose escalation up to 4 times the standard dose for inadequate response. 1, 2

First-Line Treatment

• Non-sedating second-generation H1 antihistamines are the mainstay of therapy for acute urticaria, with options including:

  • Cetirizine 10 mg daily
  • Loratadine 10 mg daily
  • Fexofenadine
  • Desloratadine
  • Levocetirizine 1, 2

• Patients should be offered at least two different non-sedating antihistamines, as responses and tolerance vary between individuals 2

• For mild cases (hives covering <10% body surface area), continue with standard dose of oral antihistamines 1

Second-Line Treatment

• For moderate cases (10-30% body surface area) or inadequate response to standard dose, increase the antihistamine dose up to 4 times the standard dose when benefits outweigh risks 1, 2

• First-generation antihistamines should generally be avoided due to sedation and anticholinergic effects 3

• Cooling antipruritic lotions (calamine or 1% menthol in aqueous cream) can provide symptomatic relief 4, 2

Third-Line Treatment

• For severe cases (>30% body surface area) or inadequate response to increased antihistamine dosing, systemic corticosteroids (prednisone 0.5-1 mg/kg/day) are recommended until hives resolve to grade 1 1

• However, recent evidence suggests that the addition of corticosteroids to antihistamines may not provide additional benefit in some cases of acute urticaria 5

• Consider same-day dermatology consultation for severe cases 1

Special Considerations

• Assess for airway compromise in cases with angioedema 1

• Consider epinephrine for severe symptoms affecting breathing in cases with angioedema, as it alleviates pruritus, urticaria, and angioedema through its action on alpha and beta-adrenergic receptors 1, 6

• Identify and minimize aggravating factors such as:

  • Overheating
  • Stress
  • Alcohol
  • Certain medications (aspirin, NSAIDs, codeine) 1, 2

• NSAIDs should be avoided in aspirin-sensitive patients with urticaria 4, 2

• ACE inhibitors should be avoided in patients with angioedema without weals 4, 2

Treatment Algorithm Based on Severity

1. Mild Acute Urticaria (<10% BSA)

   • Standard dose second-generation H1 antihistamine 1
   • Consider topical corticosteroids if needed 1

2. Moderate Acute Urticaria (10-30% BSA) or Inadequate Response

   • Increase antihistamine dose up to 4x standard dose 1, 2
   • Try alternative second-generation antihistamine if inadequate response 2

3. Severe Acute Urticaria (>30% BSA) or Inadequate Response

   • Systemic corticosteroids (prednisone 0.5-1 mg/kg/day) 1
   • Consider dermatology consultation 1
   • Rule out systemic hypersensitivity with CBC with differential and CMP 1

4. Acute Urticaria with Angioedema and Respiratory Compromise

   • Epinephrine for severe symptoms affecting breathing 1, 6
   • Continue antihistamines and add systemic corticosteroids 3

Common Pitfalls and Caveats

• Avoid first-generation antihistamines due to sedation and potential to convert minor reactions into hemodynamically significant events 3

• The course of acute urticaria is typically self-limited, with most cases resolving within 3 weeks 7

• While combination therapy with H1 and H2 antihistamines has been suggested for some refractory cases, evidence does not justify routine addition of H2-antihistamines to H1-antihistamine treatment 8

• For patients with renal impairment, avoid acrivastine in moderate renal impairment, and halve the dose of cetirizine, levocetirizine, and hydroxyzine 2

• For patients with hepatic impairment, avoid mizolastine in significant hepatic impairment 2