Pharmacology of Anticoagulation Therapy Flashcards
Anti-thrombotic drugs either ________, ________, or ________.
prevent formation of thrombi; lyse formed thrombi; inhibit formation of platelet products
Thrombi often form on ___________.
damaged endothelium, frequently from atheroslcerotic plaques; valves in the legs; or in the heart secondary to atrial fibrilation
There are three kinds of heparin: __________.
unfractionated heparin (made from pig intestine), low molecular weight heparin (depolymerized form), and fondaparinux (a synthetic pentasaccharide that corresponds to the smallest component of heparin that is an anti-coagulant)
Heparin works by ______________.
binding to anti-thrombin, which is an enzyme that deactivates the activated forms of serine proteases in the coagulation cascade; thus, heparin prevents thrombin formation
Unfractionated heparin must be given __________; however, it has the advantage of __________.
IV, because it has a poor bioavailability (it is a highly charged molecule); not crossing the placenta
Low molecular weight heparin and fondaparinux can _________.
be given subcutaneously and in outpatient settings
Heparin is used in ___________.
venous thrombosis, pulmonary embolism, abdominal surgery, management of unstable angina, acute myocardial infarction, surgery that requires cardiopulmonary bypass
Heparin can be negated with _________.
protamine sulfate; heparin is negatively charged (because of the sulfate groups) and protamine sulfate is positively charged
Heparin can also cause ____________.
thrombocytopenia, because antibodies can be made in response to platelets bound to heparin; this can be reversed with argatroban and lepirudin
The name Warfarin comes from __________.
Wisconsin alumni research foundation
Warfarin was originally used as rat poison, but it was discovered to be anti-thrombotic when _______________.
an army recruit tried to commit suicide by ingesting lots of rat poison
Warfarin is an ________________.
analog of vitamin K that competes with vitamin K for the enzyme vitamin K epoxide reductase; without vitamin K, the serine proteases cannot be carboxylated and thence cannot bind calcium
Pharmacologically, Warfarin has the advantages of ___________, and the disadvantages of ___________.
being rapidly absorbed, having a long half-life, and having high bioavailability; being teratogenic, causing hemorrhage, having drug interactions, being slow to take effect, and being genetically polymorphic
Warfarin is used to __________.
deep vein thromboses, strokes, and embolism in patients with atrial fibrilation
List the three fibrinolytic agents.
Tissue plasminogen activator, urokinase (from renal cells), and streptokinase (from Streptococcus bacteria)
