Anticoagulants Flashcards
Dabigatran
Prodrug- converted by nonspecific esterases in plasma and liver
Reversibly and competitively binds to active site of free and clot bound thrombin
Prevention of stroke and systemic embolism in atrial fibrillation
Safety- incidence of all bleeding lower than warfarin
Caution with renal impairment
Side effects: excess bleeding and dyspepsia (indigestion)
New oral anticoagulants
Independent of vitamin k
Faster than warfarin, less food drug interactions, less monitoring
Rivaroxaban
Binds to site of factor 10
Indications: primary prevention of venous thrombosis, and stroke and systemic embolism in afib pts
Mild hepatic impairment
Side effect: bleeding, musculoskeletal pain, pruitus, blister, upper abdominal pain, syncope
Apixaban
Reversible inhibitor of free and clot bound factor 10 as well as prothrombinase activity
Indications: same as other new ones
Side effect: bleeding, syncope, drug hypersensitive rash, anaphylaxis
ECT (scaring clotting time)
Measures activity of direct thrombin inhibitors ( eg dabigatran)
Metalloprotease developed from snake venom, specific activator of prothrombin
Ecarin added to plasma and time to clot is determined
Aspirin
Inhibits COX2 and thromboxane A2
Suppression of platelet inhibition lasts 7 to 10 days
Prostacyclin also inhibited but short lived!
Rapidly absorbed in GI 5-30 min peak 1 hr
Hemostasis returns in 36 hrs
GI irritation is side effect
Affective for mi and Tia
Fibrinolytics
Breaks down thrombi and thromboemboli
Streptokinase- combines with pro activator plasminogen
Urokinase-synthesized by kidney, converts plasminogen to plasminogen
Triclodioine
Inhibits platelet adhesion by interfering with the binding of fibrinogen to platelet
Metabolized by liver, excreted by kidneys
Renal impairment increases concentrations
Prevention in recurrent thrombotic stroke
Limit to pts who are intolerant or unresponsive to aspirin (neutropenia and agranulocytosis)
GI affects, leukopenia, and TTP
250-500 dosage , peak level 2 hr, complete effect = 4 days
Platelet GP 2b and 3a receptor blockers
Abciximab
Eptifibatide
Tirofiban
Block common pathway of platelet aggregation
Must be administered IV
Used for percutaneous coronary intervention and acute coronary syndromes
Dipyridamole
Inhibits adenosine uptake and cGMP phosphodiesterase activity
W/ aspirin= prevent cerebrovascular ischemia
W/ warfarin= prophylaxis for thromboemboli in prosthetic heart valve patients
Cilostazel
Phosphodiesterase inhibitor
Treatment for intermittent claudication
Hirudin
Protein from salivary glands of leech
Direct inhibitor of thrombin
Safer bc no effect on platelet function
Lepirudin
Recombinant from leech
Approved for heparin induced thrombocytopenia
Short half life and IV
Accumulates in renal insufficiency with no antidote
Bivalirudib
Rapid onset
Administered IV
Short half life
Approved for percutaneous coronary angioplasty
Argatroban
Used for heparin induced thrombocytopenia
Interfere with INR test- difficult to transfer to warfarin
Short half life IV
