====== Clopidogrel ====== Clopidogrel (also known as [[Plavix]]) is an antiplatelet drug, which means that it prevents blood cells called platelets from sticking together (aggregating) and forming blood clots A platelet [[adenosine diphosphate receptor inhibitor]]. Clopidogrel ([[Plavix]], [[Bristol-Myers Squibb]]/Sanofi-Aventis) is a prodrug requiring hepatic metabolism by [[cytochrome P450]] (CYP) isoenzymes to generate an active [[metabolite]] that is responsible for irreversible blocking of its target, the platelet [[adenosine diphosphate]] ([[ADP]]) [[P2Y12]] receptor. Numerous investigations have demonstrated a broad interindividual variability in clopidogrel-induced [[antiplatelet]] effects. Notably, patients with high on-treatment platelet reactivity (HPR) have an increased risk of recurrent ischemic events, including [[stent thrombosis]]. Genetic and environmental factors modulating hepatic metabolism of clopidogrel have shown to significantly contribute to these findings. ===== Indications ===== Clopidogrel therapy is mandatory for six weeks after [[stenting]] to allow [[endothelialization]]. ● [[Prevention]] of intra-procedural and short-term post-procedural (4–12 weeks) [[thromboembolic event]]s related to [[endovascular]] [[procedure]]s including ○ [[Coil embolization]] of wide-neck cerebral aneurysms where stent will be used ○ [[Stent]] [[implantation]] (with a second antiplatelet agent) ○ Therapeutic occlusion of large arteries (often with a second antiplatelet agent) ● Subacute management of procedural complications (alone or in combination with a second agent) ○ Parent artery coil herniations ○ Thrombus or clot on coil phenomena ○ In-stent thrombus (may be more effective than other agents). ===== Dosing ===== [[Clopidogrel Dosing]]. ===== Reversal ===== [[Platelet transfusion]]. ===== Effects of cigarette smoking on clopidogrel ===== see [[Effects of cigarette smoking on clopidogrel]].