Ticagrelor is a direct-acting, reversible, oral P2Y12 platelet adenosine diphosphate (ADP) receptor antagonist. It is a cyclopentyltriazolopyrimidine (CPTP) class antiplatelet agent that does not require metabolic activation. It is indicated for the prevention of atherothrombotic events in patients with Acute Coronary Syndrome (ACS), including those managed medically, with percutaneous coronary intervention (PCI), or with coronary artery bypass grafting (CABG).
Adult: Loading dose: 180 mg (two 90 mg tablets) as a single dose. Maintenance dose: 90 mg twice daily. Should be used with aspirin (75-100 mg daily) unless contraindicated.
Note: Administer orally with or without food. Tablet should be swallowed whole with water. Do not crush or chew. If a dose is missed, take the next dose at its scheduled time; do not take a double dose. For patients undergoing CABG, discontinue ticagrelor at least 48 hours prior to surgery if possible.
Ticagrelor and its active metabolite reversibly and selectively inhibit the P2Y12 subtype of the ADP receptor on platelets. This inhibition blocks ADP-mediated activation of the glycoprotein GPIIb/IIIa complex, which is the final common pathway for platelet aggregation. Unlike thienopyridines (e.g., clopidogrel), it is not a prodrug and does not require hepatic bioactivation.
Pregnancy: Category C: Animal studies have shown adverse effects. There are no adequate and well-controlled studies in pregnant women. Use only if the potential benefit justifies the potential risk to the fetus, considering the high risk of bleeding during delivery.
Driving: Dizziness has been reported. Patients who experience dizziness should be cautioned about driving or operating machinery.
| Aspirin (high dose >100 mg/day) | Reduces effectiveness of ticagrelor; increases bleeding risk. | Major |
| Strong CYP3A4 Inhibitors (Ketoconazole, Itraconazole, Voriconazole, Clarithromycin, Ritonavir, Saquinavir) | Significantly increases ticagrelor exposure; contraindicated. | Contraindicated |
| Strong CYP3A4 Inducers (Rifampicin, Carbamazepine, Phenytoin, Phenobarbital, St. John's Wort) | Significantly decreases ticagrelor exposure; avoid concomitant use. | Major |
| Moderate CYP3A4 Inhibitors (Diltiazem, Verapamil, Erythromycin) | Increases ticagrelor exposure; monitor for adverse effects. | Moderate |
| Other Anticoagulants/Antiplatelets (Warfarin, Heparin, Enoxaparin, Clopidogrel, Prasugrel) | Potentiates bleeding risk. | Major |
| Digoxin | Ticagrelor increases digoxin concentration (P-gp inhibition); monitor digoxin levels. | Moderate |
| Simvastatin, Lovastatin (at doses >40 mg) | Ticagrelor may increase statin exposure (CYP3A4 substrate); increased risk of myopathy. | Moderate |
| Proton Pump Inhibitors (e.g., Omeprazole) | No clinically significant interaction. Can be used for GI protection. | Minor |