Characterization of Clopidogrel Hypersensitivity Reactions and Management With Oral Steroids Without Clopidogrel Discontinuation

Abstract

Clopidogrel hypersensitivity is manifested as generalized exanthema and is caused by a lymphocyte-mediated delayed hypersensitivity in most patients. This can be managed with oral steroids without clopidogrel discontinuation. Allergenic cross-reactivity with ticlopidine, prasugrel, or both is present in a significant number of patients with clopidogrel hypersensitivity.

Management Strategies for Clopidogrel Hypersensitivity

“…Hypersensitivity may manifest as generalized, localized, or systemic reactions. Evidence suggests that the majority of patients with hypersensitivity reactions will present with generalized, cutaneous symptoms [6,7]. These generalized reactions may be an erythematous, maculopapular rash that is pruritic or urticaria without mucosal involvement [6].…”

“…These generalized reactions may be an erythematous, maculopapular rash that is pruritic or urticaria without mucosal involvement [6]. Rashes are typically distributed throughout the trunk and may involve upper and/or lower extremities [7,8]. Although less frequent than generalized reactions, localized skin hypersensitivity has also been reported [7].…”

A pharmacist’s guide to the 2012 update of the Canadian Cardiovascular Society Guidelines for the Use of Antiplatelet Therapy

“…15 Prasugrel bears some chemical similarity to other thienopyridines, and potential exists for cross-reactivity with clopidrogel. In one case series, allergenic cross-reactivity following a previous reaction to clopidrogel was observed in 24% of patients with ticlopidine, in 17% of patients with prasugrel and in 7% of patients with both ticlopidine and prasugrel 14 by skin testing. However, there are reports of successful use of prasugrel in patients with a history of clopidogrel allergy.…”

The Trouble with HARRIS (Hypersensitivity and Allergic Reactions Related to Iatrogenic Substances)

“…The necessity to collect more answers and competences on drug allergy is so deep that, for instance, even cardiologists have been compelled to investigate clopidogrel hypersensitivity by themselves and their study has not been published on an allergy journal but on a cardiology journal [10], so demonstrating the magnitude of the problem.…”