OBJECTIVES: To assess healthcare resource utilization (HCRU) among urticaria patients prior to and after omalizumab initiation in a real-world environment. METHODS: This retrospective observational cohort study utilized US claims data from the HealthCore Integrated Research Database between 09/20/2013 and 04/30/2016. The study population consisted of urticaria patients newly treated with omalizumab (defined as ≥4 omalizumab claims within the first 6 months post-index period; index date=first omalizumab claim date between 03/21/2014 and 10/31/2015), aged ≥12 years, and with ≥6 months pre- and ≥12 months post-index healthcare insurance enrollment. Descriptive and inferential statistics were used to compare all-cause and urticaria-related HCRU within 6 months pre-index (baseline) to months 1-6 and 7-12 post-index. RESULTS: The study identified 298 urticaria patients newly treated with omalizumab with a mean (SD) age of 43.5 (±13.64) years, of which 70.8% were female. The number of patients with all-cause and urticaria-related inpatient hospitalizations remained very low (n≤10) and was similar across the baseline and post-index periods (for all comparisons, p>0.05). Patients with all-cause emergency department (ED) visits decreased from 19.8% (n=59) to 14.4% (n=43) (p=0.066) and 10.7% (n=32) (p=0.001) across the baseline, months 1-6, and months 7-12 time periods, respectively. Similarly, a significant trend was observed for urticaria-related ED visits (for all comparisons, p=0.002). The number of all-cause and urticaria-related outpatient services and pharmacy claims increased significantly in the post-index period, mainly in months 1-6, when compared to those at baseline (for all baseline to months 1-6 comparisons, p<0.05). CONCLUSIONS: Study results showed that urticaria patients newly treated with omalizumab had fewer ED visits and similar inpatient hospitalizations in the post-index period, when compared to those at baseline, in a real-world clinical setting. The observed increase in post-index outpatient and pharmacy claims likely reflect the requirement that omalizumab be administered in a healthcare provider setting.