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Basophil Activation Test for Investigation of IgE-Mediated Mechanisms in Drug Hypersensitivity
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Basophil Activation Test for Investigation of IgE-Mediated Mechanisms in Drug Hypersensitivity

Published on: September 16, 2011

Allergic reactions to clopidogrel and cross-reactivity to other agents

Juzar Lokhandwala1, Patricia J M Best, Yvette Henry

  • 1First Coast Cardiovascular Institute, P.A., 3900 University Boulevard South, Jacksonville, FL 32216, USA. drjuzar@gmail.com

Current Allergy and Asthma Reports
|October 14, 2010
PubMed

Insights

Clopidogrel allergy, often a rash, affects 1% of patients after stent placement. Discontinuation increases thrombosis risk, and alternative drugs may have cross-reactivity concerns.

Area of Science:

  • Cardiology
  • Pharmacology
  • Allergy and Immunology

Background:

  • Clopidogrel is a crucial antiplatelet medication following coronary stent implantation.
  • Adverse reactions, including allergy and hematologic issues, occur in approximately 1% of patients.
  • Premature clopidogrel cessation significantly elevates the risk of stent thrombosis.

Purpose of the Study:

  • To review the implications of clopidogrel hypersensitivity reactions.
  • To discuss management strategies for clopidogrel allergy.
  • To explore alternative antiplatelet therapies in cases of clopidogrel intolerance.

Main Methods:

  • Literature review of clopidogrel hypersensitivity.
  • Analysis of adverse reaction data and management outcomes.
  • Evaluation of cross-reactivity risks with alternative antiplatelet agents.

Main Results:

  • Clopidogrel allergy commonly presents as a rash, necessitating differentiation from other causes.
  • Antihistamines and corticosteroids manage most hypersensitivity reactions.
  • Discontinuation may be required for persistent reactions, with a notable recurrence risk (up to 27%) for alternative thienopyridines like ticlopidine.

Conclusions:

  • Distinguishing clopidogrel allergy is critical to avoid unnecessary drug cessation.
  • While short-term treatments exist, some patients require alternative antiplatelet agents.
  • Cross-reactivity data for prasugrel and ticagrelor are lacking, presenting potential therapeutic avenues but requiring further investigation.

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