Glycoprotein IIb/IIIa inhibitors 

EXAMPLES 
Tirofiban, eptifibatide

MECHANISM OF ACTION 
a non-peptide antagonist that prevents fibrinogen from binding to the glycoprotein IIb/IIIa receptor, thus blocking platelet aggregation.

INDICATIONS

  • Unstable angina/non-ST elevation MI (given with aspirin and heparin).
  • Reduce the immediate risk of vascular occlusion in patients undergoing percutaneous coronary intervention

CAUTIONS AND CONTRA-INDICATIONS

  • Active bleeding.
  • Major surgery or trauma in the past 6 weeks.
  • Ischaemic stroke within 30 days or any history of haemorrhagic stroke.
  • Intracranial pathology (e.g. aneurysm, neoplasm or AV malformation).
  • Severe hypertension.
  • Deranged clotting or thrombocytopenia

SIDE-EFFECTS 

  • Bleeding.
  • Nausea.
  • Headaches.
  • Fever.
  • Reversible thrombocytopenia

METABOLISM AND HALF-LIFE 

  • t½ of tirofiban is 90min.
  • Excreted largely unchanged in the urine.

MONITORING 

  • Continuous cardiac monitoring.
  • Monitor clinically for signs of bleeding.

DRUG INTERACTIONS

  • Risk of haemorrhage is increased with heparin and antiplatelet drugs

IMPORTANT POINTS

  • Treatment should be for a minimum of 48 h a maximum of 108h if the patient remains unstable with a view to in-patient angiography and potential revascularisation as soon as possible