Antithrombotic agents Flashcards
Aspirin
MOA - irreversible inhibition of COX-1 which inhibits production of TXA2
ADR - bleeding, bronchospasm
Plavix
Clopidogrel
Thienopyridine chemical class. Irreversibly inhibits effects of ADP at the P2Y1 and P2Y12 receptor on platelet surface
Prodrug that needs to be activated
ADR - bleeding
Effient
Prasugrel
Thienopyridine chemical class. Irreversibly inhibits effects of ADP at the P2Y1 and P2Y12 receptor on platelet surface
Most likely to cause bleeding in pts with prior history of TIA or stroke, >75 y/o, <60kg
ADR - bleeding
Brilinta
Ticagrelor
Thienopyridine chemical class. Has diff chemical structure. Reversibly inhibits effects of ADP at the P2Y1 and P2Y12 receptor on platelet surface.
Can cause bradycardia and dyspnea
ADR - bleeding
Persantine
Dipyridamole
Increase cAMP levels in platelets and inhibits platelet aggregation by a series of steps
ADR - bleeding
Aggrenox
Aspirin/dipyridamole
Increase cAMP levels in platelets and inhibits platelet aggregation by a series of steps
ADR - bleeding
Anticoagulants
Interfere with the coagulation cascade
Treatment of venous thrombosis and acute arterial thrombosis, prevent stroke due to A-Fib and mechanical heart valves.
INR goal = 2.0-3.0 or 2.5-3.5
Coumadin
Warfarin
MOA - Vitamin K antagonist. Interferes with formation of several clotting factors. Inhibits Vitamin K from being reduced by Vit. K epoxied reductase
1st oral coagulant
1/2 life ~60 hours. Needs about 3-7 days to take full effect
Dose needs to be individualized for each patient
Antidote: Vit. K, phytonadione
Heparin
Unfractioned heparin (UFH)
High molecular weight heparin
Enhances the activity of antithrombin leading to inactivation of factor Xa, thrombin and other clotting factors.
Antidote is protamine.
Dosed in units not mg. Not to be given IM due to risk of bleeding into muscle.
Can cause heparin-induced thrombocytopenia.
Lovenox
Enoxaparin
Low molecular weight heparin (LMWH) binds more selectively to factor Xa and thrombin than UFH, enhances effects of antithrombin.
Antidote: protamine is partial antidote.
Less likely to cause heparin-induced thrombocytopenia. Available in refilled syringes.
Xarelto
Rivaroxaban
Direct factor Xa inhibitor without the need for antithrombin
Direct Oral Anticoagulant (DOAC)
Not approved for pts with mechanical heart valves.
Rapid onset of action (1-4 hours)
Eliquis
Apixaban
Direct factor Xa inhibitor without the need for antithrombin
Direct Oral Anticoagulant (DOAC).
Not approved for pts with mechanical heart valves.
Rapid onset of action (1-4 hours)
Savaysa
Edoxaban
Direct factor Xa inhibitor without the need for antithrombin
Direct Oral Anticoagulant (DOAC).
Not approved for pts with mechanical heart valves.
Rapid onset of action (1-4 hours).
Pradaxa
Dabigatran
Direct thrombin inhibitor. Binds directly to thrombin and blocks its activity without the need for antithrombin.
Direct Oral Anticoagulant (DOAC).
Not approved for pts with mechanical heart valves.
Rapid onset of action (1-4 hours).
Fibrinolytics or clot busters
Activate conversion of plasminogen to plasmin which digests the fibrin clot.
ONLY AGENTS THAT DISSOLVE CLOTS!!!
Administered IV.
Risk of bleeding is 2-3 times greater than with heparin so it’s reserved for situations when potential benefits outweigh substantial risks for bleeding.
