Mechanism of action Like the thienopyridines prasugrel, clopidogrel and ticlopidine,<unk>  blocks adenosine diphosphate (ADP) receptors of subtype P2Y12. In contrast to the other antiplatelet drugs,<unk>  has a binding site different from ADP, making it an allosteric antagonist, and the blockage is reversible. Moreover, the drug does not need hepatic activation, which might work better for patients with genetic variants regarding the enzyme CYP2C19 (although it is not certain whether clopidogrel is significantly influenced by such variants). More recently,<unk>  was found to result in a lower risk of stroke at 90 days than clopidogrel, which requires metabolic conversion, among Han Chinese CYP2C19 loss-of-function carriers with minor ischemic stroke or TIA. Pharmacokinetics<unk>  is absorbed quickly from the gut, the bioavailability being 36%, and reaches its peak concentration after about 1.5 hours. The main metabolite, AR-C124910XX, is formed quickly via CYP3A4 by de-hydroxyethylation at position 5 of the cyclopentane ring. It peaks after about 2.5 hours. Both<unk>  and AR-C124910XX are bound to plasma proteins (>99.7%), and both are pharmacologically active. Blood plasma concentrations are linearly dependent on the dose up to 1260 mg (the sevenfold daily dose). The metabolite reaches 30–40% of<unk> 's plasma concentrations. Drug and metabolite are mainly excreted via bile and feces. Plasma concentrations of<unk>  are slightly increased (12–23%) in elderly patients, women, patients of Asian ethnicity, and patients with mild hepatic impairment. They are decreased in patients that self-identified as 'black' and those with severe renal impairment. These differences are not considered clinically relevant. In Japanese people, concentrations are 40% higher than in Caucasians, or 20% after body weight correction. The drug has not been tested in patients with severe hepatic impairment. Consistently with its reversible mode of action,<unk>  is known to act faster and shorter than clopidogrel. This means it has to be taken twice instead of once a day which is a disadvantage in respect of compliance, but its effects are more quickly reversible which can be useful before surgery or if side effects occur.
Ticagrelor
Clopidogrel
Ticlopidine
Prokarin
Rivaroxaban
Eptifibatide
Apixaban
Palladin