Antiplatelet Agents


Drug Dosage Remarks
Aspirin1 Loading dose: Chew 150-325 mg non-enteric-coated x 1 dose followed by: 
Maintenance dose: 75-100 mg PO 24 hourly
Maintenance dose if combined with Clopidogrel/Ticagrelor:
75-100 mg PO 24 hourly
Adverse Reactions
  • GI effects (GI upset which may be minimized by administering with food and with use of enteric-coated formulation, also GI irritation including erosion, ulceration, etc); Hematologic effects (increased bleeding time, decreased platelet adhesiveness, hemorrhage); Hypersensitivity reactions
Special Instructions
  • Contraindicated in patients with active pathological bleeding (eg peptic ulcer, intracranial hemorrhage), known allergy, hemophilia, hemorrhagic disorders, severe renal or hepatic impairment
  • Ensure that benefit outweighs the risk prior to use in combination with Warfarin, Heparin, thrombolytics, NSAIDs and other drugs that increase the risk of bleeding
Cangrelor PCI for ACS patients:
30 mcg/kg IV bolus prior to PCI followed by 4 mcg/kg/minute continuous IV infusion over at least 2 hours or for the duration of the PCI, whichever is longer 
Adverse Reactions
  • Hematologic effect (hemorrhage/bleeding); Other effects (renal impairment, dyspnea, hypersensitivity reaction)
Special Instructions
  • Contraindicated in patients with active pathological bleeding
  • An oral P2Y12 platelet inhibitor must be administered after Cangrelor infusion to maintain platelet inhibition
Clopidogrel Co-administered with Aspirin:
Loading dose: 300 mg PO followed by 75 mg PO 24 hourly 
PCI for ACS patients:
300-600 mg PO loading dose prior to or at the time of PCI, followed by 75 mg PO 24 hourly
Adverse Reactions
  • Hematologic effects (hemorrhage, purpura, epistaxis; blood dyscrasias, including neutropenia, thrombotic thrombocytopenic purpura have occurred); Dermatologic effects (rash, pruritus); GI effects (abdominal pain, nausea/vomiting, dyspepsia, constipation)
Special Instructions
  • Contraindicated in patients with active bleeding or severe liver impairment
  • Concurrent use of drugs known to inhibit CYP2C19 (eg Omeprazole, Esomeprazole, Cimetidine, Fluconazole, Ketoconazole, Voriconazole, Etravirine, Felbamate, Fluoxetine, Fluvoxamine and Ticlopidine) should be avoided
    • Separating the time of administration between the drugs does not reduce the chance of interaction 
Prasugrel Co-administered with Aspirin:
Loading dose: 60 mg PO followed by 
Maintenance dose:
<60 kg:
5 mg PO 24 hourly x 12 months
≥60 kg: 10 mg PO 24 hourly x 12 months 
Adverse Reactions
  • GI effects (nausea/vomiting, diarrhea); Dermatologic effect (rash); Hepatic effects (elevated LFT, rarely hepatitis and cholestatic jaundice); Hematologic effects (neutropenia, thrombotic thrombocytopenic purpura, agranulocytosis, hemorrhage)
Special Instructions
  • Contraindicated in patients with active bleeding, hemorrhagic diatheses, history of leukopenia, thrombocytopenia or agranulocytosis, history of stroke or TIA, severe hepatic impairment
  • Use with caution in patients with hepatic impairment or when combining with Warfarin, Heparin, thrombolytics, NSAIDs and other drugs that increase the risk of bleeding
Ticagrelor Co-administered with Aspirin:
Loading dose:
 180 mg PO followed by
Maintenance dose: 90 mg PO 12 hourly x 12 months
When an extended treatment is required for patients with a history of MI of at least 1 year and a high risk of an atherothrombotic event:
60 mg PO 12 hourly 
Adverse Reactions
  • Hematologic effect (bleeding); Respiratory effect (dyspnea); CNS effects (headache, dizziness); ENT effects (epistaxis, vertigo); GI effects (abdominal pain, nausea/vomiting, constipation, diarrhea); Metabolic effect (hyperuricemia); Dermatologic effects (rash, pruritus); Other effect (post-procedural hemorrhage)
Special Instructions
  • Contraindicated in patients with active pathological bleeding, intracranial hemorrhage history, known allergy, or severe hepatic impairment
  • Use with caution in patients with increased risk for bradycardia
  • Avoid abrupt discontinuation of therapy or therapy lapses
Triflusal  600 mg/day PO in single or divided doses 
or
900 mg/day PO in divided doses  
Adverse Reactions
  • GI effects (dyspepsia, nausea/vomiting, abdominal pain, constipation, flatulence); Other effects (anorexia, headache)
Special Instructions
  • Contraindicated in patients with hypersensitivity to other salicylates, active, antecedent or complicated peptic ulcer or other active pathological bleeding
  • Use with caution in patients with renal or hepatic impairment, increased risk of bleeding from trauma or other pathological conditions, ASA- or other NSAID-induced lesions
  • Discontinue use 7 days prior to surgery
1Combinations of Aspirin/Glycine and Aspirin/Clopidogrel are available. Please see the latest MIMS for specific formulations and prescribing information.