Management of Urticaria
Initial diagnostic testing
- Complete blood count with differential
- ESR or CRP
- Infectious disease workup (symptom-directed only; this is particularly important in children because of the high frequency of streptococcal or mycoplasma infection in association with urticaria)
- Diagnostic maneuvers for cold or physical urticaria
- Only limited additional testing as indicated by history and/or physical exam
First-line therapy: non-sedating H1-antihistamines (second generation)
- Start with standard dosing
- Escalate up to 4-fold dosing
- Add a second agent
- Treat with a non-sedating H1 antagonist antihistamine:
- Loratadine (such as Claritin) 10 mg
- Fexofenadine (such as Allegra) 180 mg
- Cetirizine (such as Zyrtec) 10 mg
- Levocetirizine (such as Xyzal) 2.5 mg
- Consider escalating the dose up to 4-fold dosing after 2 weeks. There is current data supporting that dose-escalation is effective for some, but not all, non-sedating H1 antihistamines.
- If urticaria is suppressed, treat the patient continually in order to maintain control of the process, with a slow taper once symptoms fully subside.
- Systemic steroids (such as prednisone) may be necessary for 3-7 days for severe, acute flares.
- Sedating H1 antagonist antihistamines are no longer recommended as first-line or long-term treatment of urticaria because of adverse effects associated with their use (such as sedation, anticholinergic effects) and due to the high efficacy and wide availability of non-sedating antihistamines.
- Hydroxyzine (such as Atarax) 25 mg t.i.d. or q.i.d. with gradual dose escalation every 3-4 days to a maximum of 200 mg/day.
- Diphenhydramine (such as Benadryl) 25 mg t.i.d. or q.i.d.
- Doxepin (such as Sinequan). Begin therapy with 25 mg b.i.d. and increase the dose every 4-5 days to a maximum of 50 mg t.i.d. Because doxepin can prolong the PR interval and worsen conduction defects, obtain an EKG prior to therapy.
- Add a leukotriene inhibitor, like montelukast (such as Singulair) 10 mg q day
- There is some evidence to support addition of other agents such as:
- H2 antagonist antihistamine (such as ranitidine, famotidine, cimetidine)
- Cyclosporine (such as Neoral or Sandimmune)
- Hydroxychloroquine (such as Plaquenil)
- Omalizumab (such as Xolair)
- A regimen with multiple agents in combination may be necessary to control symptoms.
When to refer to a dermatologist
- If the diagnosis of urticaria is unclear.
- For clarifying the diagnosis in rare cases of urticaria clearly in association with systemic symptoms (i.e., arthritis, fever, bone pain, paraproteinemia, ocular or other neurologic symptoms).
- For long-term management of long-term urticaria, especially if it is highly steroid-dependent.