title: Prasugrel use in a patient allergic to clopidogrel: effect of a drug shortage on selection of dual antiplatelet therapy.
abstract: OBJECTIVE
  A case illustrating multiple considerations in choosing safe and effective dual antiplatelet therapy for a patient with a history of clopidogrel allergy-including concerns relating to a national drug shortage-is described.
  
  
  CONCLUSIONS
  A 75-year-old woman required dual antiplatelet therapy (aspirin plus a thienopyridine) after a cardiac catheterization procedure; during a prior emergency department visit for acute coronary syndrome, she had experienced an allergic reaction within 24 hours of receiving dual therapy including clopidogrel. A team of pharmacy and allergy staff determined that challenging the patient with prasugrel was the best treatment option. Key considerations in the decision-making process included (1) concerns that an alternative thienopyridine, ticlopidine, might be unavailable for long-term outpatient use due to an ongoing national drug shortage, (2) the patient's concomitant use of metoprolol (cessation of β-blocker use is recommended for four days before attempted clopidogrel desensitization), and (3) recent reports of the safe use of prasugrel in three patients with a history of clopidogrel allergy. In the case described here, prasugrel administration was effective and did not result in adverse effects; however, the risk of cross-reactivity of clopidogrel and ticlopidine or prasugrel remains largely unknown. The case highlights the importance of careful consideration of a number of patient- and drug-specific factors in the selection of the most appropriate antiplatelet dual therapy for patients with a history of allergic reactions to clopidogrel.
  
  
  CONCLUSIONS
  A shortage of ticlopidine prompted the use of prasugrel in a clopidogrel-allergic patient requiring dual antiplatelet therapy. Prasugrel therapy was well tolerated, with no evidence of allergic reaction.
authors: Department of Pharmacy, Tufts Medical Center, Boston, MA 02111, USA.
authors: Erika
authors: E
authors: Felix-Getzik
authors: Lynne M
authors: LM
authors: Sylvia
mesh_terms: D000368:Aged; D000077144:Clopidogrel; D004342:Drug Hypersensitivity / Q000175:diagnosis* / Q000188:drug therapy; D004359:Drug Therapy, Combination; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D010879:Piperazines / Q000008:administration & dosage*; D010975:Platelet Aggregation Inhibitors / Q000008:administration & dosage / Q000009:adverse effects*; D000068799:Prasugrel Hydrochloride; D013876:Thiophenes / Q000008:administration & dosage*; D013988:Ticlopidine / Q000008:administration & dosage / Q000009:adverse effects / Q000031:analogs & derivatives*
chemical_list: D010879:Piperazines; D010975:Platelet Aggregation Inhibitors; D013876:Thiophenes; D000077144:Clopidogrel; D000068799:Prasugrel Hydrochloride; D013988:Ticlopidine