Clopidogrel (Plavix)

Clopidogrel (Plavix)


February 24, 2023

Dear Colleagues,

Welcome to this UH EMS-Institute Pharmacy Phriday CE offering. Last week’s offering discussed Alpha and Beta medications and how they work within the body. In this installment, we look at a few common medications that are classified as an antiplatelet.  

We all know platelets are an important component of blood and circulate freely throughout the bloodstream. They are relatively inactive until a chemical messenger is introduced, many times by injury to a blood vessel. At that point, the platelets activate and begin to aggregate and clump together. These can create a thrombus if they attach to a vessel wall or an embolus as they move through the body, looking for smaller vessels to occlude. 

In emergency medicine, platelet inhibitors impair the formation and progression during a thrombotic event. An important part of the platelet activation process is the interaction of adenosine diphosphate (ADP) with the platelet P2Y12 receptor. Plavix irreversibly blocks ADP from binding to those receptors. Within the UH protocols, Brilinta is the preferred P2Y12 inhibitor. Plavix would only be used in cases when Brilinta is not available and would be introduced with just-in-time training reviewing the specifics of this “Special-Use Medication.”

An area the provider is more likely to encounter Plavix is as a prescription that a patient may be taking regularly. It is a common medication for patients who have had a recent MI, stroke, or been diagnosed with peripheral vascular disease.  Plavix was, in fact, in the top 20 medications prescribed in 2022 per one survey [1]. Remember that the regular use of Plavix, or any other antiplatelet medication, would preclude the use of Brilinta within the ACS protocol. Within the 2023 UH protocols, a list of common antiplatelets and anticoagulants has been clarified and is listed for the provider’s reference.

With the use of Plavix, there is an increased risk of bleeding. Therefore, bleeding in the patient is a contraindication to its use. Other than bleeding, another common adverse reaction to its use includes an allergic or anaphylactic reaction. The route of administration is oral, and the dose is 600 mg.

Until the next time, stay safe.


The UH EMS-I Team

University Hospitals