Cetirizine better than diphenhydramine for acute urticaria treatment

USA: Intravenous cetirizine is a better alternative to intravenous diphenhydramine for the treatment of acute urticaria, finds a recent study in the journal Annals of Emergency Medicine. Benefits of intravenous cetirizine over diphenhydramine include less sedation, lower rates of revisit to the treatment center, shorter time spent in treatment center, and fewer adverse effects.

Acute urticaria is urticaria that occurs with or without angioedema that persists for less than 6 weeks. It is a frequent presentation in emergency departments (EDs), urgent care centers, and other clinical areas. Diphenhydramine is the only intravenous antihistamine offered for its treatment because of its short duration of action and well-known adverse effects. Benjamin S. Abella, University of Pennsylvania, Philadelphia, PA, and colleagues evaluated cetirizine injection, the first second-generation injectable antihistamine, for acute urticaria.

The researchers conducted a multicenter, randomized, noninferiority, phase 3 clinical trial. It included adults presenting to EDs and urgent care centers with acute urticaria requiring an intravenous antihistamine. They were randomized to receive either intravenous cetirizine 10 mg or intravenous diphenhydramine 50 mg.

The primary endpoint was the 2-hour pruritus score change from baseline, with time spent in the treatment center and rate of return to treatment centers as key secondary endpoints.