Levocetirizine and Prednisone Are Not Superior to Levocetirizine Alone for the Treatment of Acute Urticaria: A Randomized Double-Blind Clinical Trial.

STUDY OBJECTIVE We evaluate the efficacy of a 4-day course of prednisone added to antihistamine for the management of acute urticaria in an emergency department (ED). METHODS In this double-blind randomized clinical trial, patients were eligible for inclusion if aged 18 years or older and with acute urticaria of no more than 24 hours' duration. Patients with anaphylaxis or who had received antihistamines or glucocorticoids during the previous 5 days were not included. In addition to levocetirizine (5 mg orally for 5 days), patients were assigned to receive prednisone (40 mg orally for 4 days) or placebo. The primary endpoint of the study was itching relief 2 days after the ED visit, rated on a numeric scale of 0 to 10. Secondary endpoints were rash resolution, relapses, and adverse events. RESULTS A total of 100 patients were included, 50 in each group. Seven patients in the prednisone group and 8 in the placebo group discontinued treatment. At 2-day follow-up, 62% of patients in the prednisone group had an itch score of 0 versus 76% of those in the placebo group (Δ 14%; 95% confidence interval -31% to 4%). Thirty percent of patients in the prednisone group and 24% in the placebo group reported relapses (Δ 6%; 95% confidence interval -23% to 11%). Mild adverse events were reported by 12% of patients in the prednisone group and 14% in the placebo group. CONCLUSION The addition of a prednisone burst did not improve the symptomatic and clinical response of acute urticaria to levocetirizine. This study does not support the addition of corticosteroid to H1 antihistamine as first-line treatment of acute urticaria without angioedema.