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.
Key findings of the study include:
- Among 262 enrolled patients, the 2-hour pruritus score change from baseline for intravenous cetirizine was statistically noninferior to that for intravenous diphenhydramine (–1.6 versus –1.5), and in favor of cetirizine.
- Treatment differences also favored cetirizine for mean time spent in treatment center (1.7 versus 2.1 hours), return to treatment center (5.5% versus 14.1%), lower change from baseline sedation score at 2 hours (0.1 versus 0.5), and adverse event rate (3.9% versus 13.3%).
"Intravenous cetirizine is an effective alternative to intravenous diphenhydramine for treating acute urticaria, with benefits of less sedation, fewer adverse events, shorter time spent in treatment center, and lower rates of revisit to treatment center," concluded the authors.
The study, "Intravenous Cetirizine Versus Intravenous Diphenhydramine for the Treatment of Acute Urticaria: A Phase III Randomized Controlled Noninferiority Trial," is published in the journal Annals of Emergency Medicine.
DOI: https://doi.org/10.1016/j.annemergmed.2020.05.025
