Tegretol and aspirin are both platelet inhibitors used to treat conditions such as heart attacks or angina. However, they differ in that they act on different targets of the platelet adhesion reaction. Aspirin mainly inhibits platelet activation and aggregation by irreversibly inhibiting platelet cyclooxygenase 1 to block the production of thromboxane 2. Aspirin has no effect on platelet aggregation induced by adenosine diphosphate and collagen, while Tegretol inhibits platelet aggregation induced by the release of ADP from activated platelets by inhibiting platelet adenosine 2 phosphate receptors, both of which act on different targets and have similar effects. However, when used together, all targets are inhibited, resulting in a better antiplatelet effect, but also making the risk of bleeding higher.