Abstract 14860: Frequency of Allergic or Hematologic Adverse Reactions to Prasugrel in Patients with a Previous Allergic or Hematologic Adverse Reaction to Clopidogrel
Background. Among patients allergic to the second-generation thienopyridine clopidogrel, the frequency of allergic cross reactivity to the first-generation thienoyridine ticlopidine is high (~28%). Because allergic reactions to the third thienopyridine, prasugrel, have also been reported among patients allergic to clopidogrel, the Food and Drug Administration required that physicians be warned about the possibility of allergic reactions to prasugrel among such patients. No formal studies have been reported.
Objectives. We sought to analyze the frequency of allergic reactions to prasugrel among patients allergic to clopidogrel.
Methods and Results. We analyzed the pharmacy database and medical records of all patients at Geisinger Clinic (Danville, PA), VA North Texas Healthcare System (Dallas, TX), Mayo Clinic (Rochester, MN), and Intermountain Medical Center (Murray, UT) who had suffered a definite or probably allergic reaction to clopidogrel and who subsequently received prasugrel. Patient demographics, details of adverse reactions, and subsequent clinical course were reviewed. Out of a total of more than 160 patients described as having had an allergic reaction to clopidogrel, 45 patients were confirmed (blinded to response to prasugrel) to have suffered an allergic or hematologic adverse reaction to clopidogrel. No patient suffered an allergic reaction to prasugrel (95% confidence intervals 0%, 7.0%).
Conclusions. In patients with an allergic or hematologic reaction to clopidogrel, the frequency of allergic reactions to prasugrel is low (zero in this study), and lower than has been reported with those receiving clopidogrel who subsequently receive ticlopidine.
- © 2012 by American Heart Association, Inc.