Papers of the Week

The incidence of opioid allergy cross-reactivity in hospitalized patients with historical opioid allergies remains unknown. The purpose of this study was to characterize the incidence of newly suspected IgE-mediated reactions (IMRs) based on clinical criteria among patients with a chart-documented opioid allergy and to assess clinician perceptions of opioid allergies. This retrospective cohort study was conducted in hospitalized adults with a historically documented opioid allergy who received a subsequent opioid. The primary outcome was the incidence of allergic cross-reactivity between clinical and chemical opioid classes in patients with historical IMRs (H-IMRs) identified by clinical criteria, ICD-9 diagnosis codes, or allergic reaction treatment. Secondary outcomes included the incidence of opioid intolerances incorrectly documented as allergies and a survey to clinicians to assess the impact of opiate warnings on prescribing practices. A total of 499 patients with historical opioid allergies were included. H-IMR to an opioid of any class was not significantly associated with IMR cross-reactivity to the same or any other class, with cross-reactivity rates ranging from 0% to 6.7%. Of the historical chart-documented allergies, 249 reactions (50%) were determined to be intolerances. A total of 461 (92.5%) patients successfully tolerated readministration of opioids despite a chart-documented allergy, and 8 (1.6%) patients developed possible IMR (7 pruritus, 1 possible anaphylaxis). Survey results (n = 54) indicated that opiate allergy warnings were neutral or unlikely to change opiate prescribing. The risk of IMRs caused by opioids is low in patients with H-IMRs to opioids. Opioid allergy documentations may propagate alert fatigue and unwarranted prescribing changes.