What are the symptom management options for urticaria?

Symptom Management for Urticaria

Second-generation H1-antihistamines at standard doses are the first-line treatment for urticaria, with dose escalation up to 4 times the standard dose for inadequate response, followed by add-on therapies such as omalizumab for refractory cases. 1

Stepwise Treatment Approach

First-Line Treatment

• Start with standard-dose second-generation H1-antihistamines:
  • Fexofenadine 180mg
  • Cetirizine 10mg
  • Loratadine 10mg
  • Desloratadine
  • Bilastine
  • Levocetirizine 1

Second-Line Treatment

• If inadequate response after 2-4 weeks, increase dose up to 4 times the standard dose
• Higher doses have shown improved symptom control in approximately 75% of difficult-to-treat urticaria cases without compromising safety 2
• For example:
  • Cetirizine up to 40mg daily
  • Fexofenadine up to 720mg daily 1

Third-Line Treatment

• For patients who remain symptomatic despite up-dosed antihistamines:
  • Add omalizumab (300mg every 4 weeks or 600mg every 2 weeks)
    • FDA-approved for chronic spontaneous urticaria in adults and adolescents 12 years and older 1
    • Monitor for potential anaphylaxis
  • Alternative: Add leukotriene receptor antagonists (e.g., montelukast) 1

Fourth-Line Treatment

• For refractory cases:
  • Cyclosporine (up to 5mg/kg body weight)
    • Requires monitoring of blood pressure and renal function every 6 weeks
    • Potential risks include hypertension, epilepsy in predisposed individuals, hirsutism, gum hypertrophy, and renal failure 1

Additional Therapeutic Options

Combination Therapy

• H1 + H2 antihistamine combination has shown better efficacy than H1 antihistamines alone, particularly for symptomatic dermographism 1, 3
  • Example: Diphenhydramine (50mg IV) plus ranitidine (50mg IV) or cimetidine (300mg IV) 4

Topical Treatments

• Topical doxepin may provide relief but should be limited to 8 days and 10% of body surface area (maximum 12g daily) due to risk of allergic contact dermatitis 1

First-Generation Antihistamines

• Use cautiously due to sedative effects
• May be useful for nighttime symptoms when pruritus interferes with sleep 1

Management of Acute Urticaria with Anaphylaxis

If urticaria is accompanied by signs of anaphylaxis:

1. Administer epinephrine 0.3mg IM in mid-anterolateral thigh immediately 1, 5
   • Epinephrine acts on both alpha and beta-adrenergic receptors
   • Lessens vasodilation and vascular permeability
   • Causes bronchial smooth muscle relaxation
   • Alleviates pruritus, urticaria, and angioedema 5
2. Follow with combined H1+H2 blockade:
   • Diphenhydramine (1-2 mg/kg or 25-50 mg IV)
   • Ranitidine (50 mg IV) 1
3. Seek immediate emergency medical attention 1

Special Considerations

Monitoring Disease Control

• Use validated tools like the Urticaria Control Test (UCT) and Urticaria Activity Score (UAS7)
• A UCT score of 4 indicates poorly controlled disease
• A UCT score ≥12 indicates well-controlled disease 1

Step-Down Therapy

• Consider step-down only after at least 3 consecutive months of complete control
• Reduce antihistamine dose gradually (not more than 1 tablet per month) 1

Pediatric Patients

• Start with age-appropriate dosing of second-generation H1-antihistamines
• Medication dosing must be weight-based
• Food allergies are a common cause of urticaria in infants 1

Common Pitfalls and Caveats

1. Avoid prolonged use of first-generation antihistamines due to significant sedative and anticholinergic effects 3

2. The role of systemic corticosteroids remains unclear in the treatment of acute urticaria. Recent studies show that adding prednisone to antihistamines did not improve symptoms compared to antihistamine alone in two out of three RCTs 4

3. Don't undertreat with inadequate antihistamine doses - many patients require higher than standard doses for symptom control 2

4. Don't overlook potential anaphylaxis - epinephrine is the first-line treatment if urticaria is accompanied by signs of anaphylaxis 1, 5

5. Recognize when to refer to specialists - patients with refractory urticaria, suspected urticarial vasculitis, or those requiring third-line therapies should be referred to dermatology or allergy specialists 1