Ticagrelor

Ticagrelor is an oral antiplatelet medication that inhibits platelet aggregation by reversibly binding to the P2Y12 receptor on platelets. It belongs to the non-thienopyridine class and differs from clopidogrel and prasugrel in that it is not a prodrug and its antiplatelet effects are reversible, with a relatively rapid onset and offset.

Pharmacology and mechanism: Ticagrelor acts directly on the P2Y12 receptor to prevent adenosine diphosphate–mediated platelet activation. Its effects are achieved with the parent drug and an active metabolite produced mainly via CYP3A4. The onset of antiplatelet action is rapid, and the drug has a half-life on the order of about 7–12 hours, allowing effects to change more quickly after discontinuation compared with irreversible inhibitors.

Clinical use: Ticagrelor is indicated to reduce the rate of cardiovascular death, myocardial infarction, and stroke in adults with acute coronary syndrome, including ST-elevation and non-ST-elevation ACS, in addition to aspirin. It can be used in patients managed medically or those undergoing percutaneous coronary intervention (PCI). Dosing typically involves a loading dose of 180 mg, followed by maintenance therapy of 90 mg twice daily; after 12 months, a lower continuation dose of 60 mg twice daily may be considered to reduce bleeding risk.

Safety and interactions: The most common adverse effects are bleeding and dyspnea. Other potential risks include bradyarrhythmias and elevated uric acid. Ticagrelor is contraindicated in patients with active major bleeding and in those with a history of intracranial hemorrhage. It interacts with strong CYP3A4 inhibitors or inducers and with certain statins; caution is advised with nonsteroidal anti-inflammatory drugs due to increased bleeding risk. Brand names include Brilinta in many markets.