At a Glance
Glycoprotein IIb/IIIa inhibitors in clinical use include tirofiban (Aggrastat), eptifibatide (Integrilin), and abciximab (ReoPro). These compounds are very potent antiplatelet agents. They are commonly used in procedures involving cardiac catheterization. In a small percentage of cases, these drugs can also induce a significant thrombocytopenia, with platelet counts often less than 10,000 per micrometer. Inhibition of platelets with glycoprotein IIb/IIIa inhibitors involves a different mechanism from that produced by aspirin, NSAIDs, such as ibuprofen, Plavix, and Prasugrel. Therefore, treatment of patients with glycoprotein IIb/IIIa inhibitors, along with other antiplatelet agents, commonly produces highly significant platelet inhibition that predisposes the patient to major bleeding.
What Tests Should I Request to Confirm My Clinical Dx? In addition, what follow-up tests might be useful?
Unlike other platelet inhibitors, particularly clopidogrel (Plavix), to which some patients do not respond and, therefore, may require a platelet function study to determine if the drug is working, it would be extremely rare to require documentation of platelet inhibition by glycoprotein IIb/IIIa inhibitors.
Are There Any Factors That Might Affect the Lab Results? In particular, does your patient take any medications – OTC drugs or Herbals – that might affect the lab results?
If a patient experiences severe thrombocytopenia on exposure to a glycoprotein IIb/IIIa inhibitor, bleeding in association with the use of this compound may be a result of both an adequate platelet number and a defect in platelet function produced by the drug.
What Lab Results Are Absolutely Confirmatory?
If there is any reason to suspect a glycoprotein IIb/IIIa inhibitor is not inhibiting platelet function, any of the variety of platelet function studies available should determine whether the drug is effective.
Copyright © 2017, 2013 Decision Support in Medicine, LLC. All rights reserved.
No sponsor or advertiser has participated in, approved or paid for the content provided by Decision Support in Medicine LLC. The Licensed Content is the property of and copyrighted by DSM.
