1-hour Premedication for Allergy Goal in Emergency: PAGE-1 is a prospective, parallel, two-arm, non-inferiority, randomized controlled trial evaluating the safety of a 1-hour (intervention) versus a 4-hour (standard regimen) intravenous (IV) premedication protocol in adult patients in the Emergency Department (ED) with a documented iodinated contrast allergy and requiring computed tomography (CT) imaging for a high-risk indication.

Allergic or hypersensitivity reactions to iodinated contrast media are rare, estimated to occur in 0.3% to 1.4% of cases, but have decreased significantly after the switch from high-osmolar to low-osmolar contrast. Most reactions are mild, and breakthrough reactions occur regardless of the timing of premedication. IV premedication is recommended, but there is no level I evidence for its basis in the ED.

This study addresses the sparse evidence that underpins the ubiquitous multi-hour premedication protocols in EDs nationwide. It specifically challenges the existing paradigm of 4-5 hours of IV premedication, which has remarkably never been prospectively validated.

Inclusion Criteria:

1. Adult (≥ 21 years old)
2. Documented iodinated contrast allergy in the electronic health record
3. CT with iodinated contrast ordered for a high-risk indication, † defined as post-arrest, concern for aortic dissection, ischemia, occlusion, obstruction, or other life-threatening conditions requiring timely diagnosis
4. Willing and able to give consent

Exclusion Criteria:

1. Previous enrollment in this study
2. Pregnancy
3. Seafood or iodine allergy, alone
4. Gadolinium allergy

Study protocol and statistical plan

Available after start date and 1 year after end of study

Study coordinators and key personnel