IMPACT ADP reagent is used to detect platelet dysfunction in whole blood via the P₂Y₁₂ activation pathway of platelets.

The P₂Y₁₂ receptors are the target of antiplatelet drugs such as clopidogrel, prasugrel, ticagrelor, and cangrelor. These drugs block the binding of ADP to the P₂Y₁₂ receptor, thereby inhibiting platelet activation and aggregation to prevent and treat thromboembolic diseases (such as heart attack and stroke).

ADP plays an important role in both primary (initial) and secondary (enhanced) platelet aggregation.

ADP binds to the P₂Y₁₂ receptors, leading to the activation of glycoproteins. The released ADP molecules, in turn, stimulate the activation of other platelets, thus increasing aggregation.

ADP plays a crucial role in haemostasis by promoting platelet aggregation at the site of injury.

Excessive platelet activation mediated by ADP can lead to thrombosis (blood clot formation) and embolism (blood clots moving from one site to another).