hemeagents2pharm Flashcards
what is lepirudin
a recombinant form of hiruden is a direct thrombin inhibitor DTI
what is hirudin
isolated from the leach first DTI direct thrombin inhibitor
name some direct thrombin inhibitors
hirudin lepirudin, bivalrudin, and argatroban all the parental orally is only dabigatran
what can inhibit thrombin when its bound to fibrin
only the direct thrombin inhibitors or DTI
what drug would you use with a patient with a history of thrombocytopinea
you would use a DTI because it does not cause thrombocytopinea
what DTI would you use with a PCI in patients with HIT
bivalirudin
what DTI would you use with a stroke prevention patient
Dabigatran
what is a drawback on DTI
we do not currently have a direct antidote
what are some clinical uses of warfarin
prevent progression of venous thrombosis and thromboembolism and MI and can be used orally
tell me about the warfarin mechanism of action
it will compete with vitamin k for binding sites and will prevent clotting faxtors 2,7,9, and 10 by preventing the vit k reduction.
tell me about the pharmacokinetics of warfarin
Almost 100% bioavaliibility F, but its highly bound to serum albumin but only the unbound is active. Half life 48 hours so theraputic after 3-5 days and takes 5-7 days to leave system after stopping the dosafe
tell me about the warfarin clearance
liver metabolized by the p450 complex, know that some patients will need less because of a common genetic variat that clears it slower.
what assay would you use to monitor warfarin
prothrombin time assay is generally used. The normal INR is 2.0-3.0 can be higher with mechanical heart valves.
tell me about the drug interaction with warfarin
broad spectrum antibiotics will increase the effect of warfarin, nonsteroidal anti-inflammatory drugs increase effect, certain SSRI can increase, certain statins can increase, rifampin barbiturates anc carbamazepine all decrease the effects of warfarin.
tell me about other factors that effect warfarin
lower liver function will increase warfarin, disease of intestine like crohns will increase effects, renal insufficiency can cause hyoalbuminimen will increase warfarin.
what are some adverse effects of warfarin
hemorrhage, placental transfer, birth defects, necrosis,
what can reverse the effects of warfarin
vitamin K can be used but is slow otherwise you have to use fresh plasma.
what are the new oral anticoagulants
rivaroxaban, apixaban, dabigatran.
what are the benefits of the new oral over warfarin
faster onset longer indow low potential for interactions, less monitering, lower risk of intracranera or intecerebral bleeding
tell me about rivaroxaban
oral direct factor of Xa inhibitor,
what is the major antiplatelet drug
aspirin,
how does aspirin work to reduce platelets
reduces thrombane A2 production which leads to a reduced platelets activation and aggregation and is an irreversible blocker.
how does dipyridamole work
blocks cAMP reduction leading to higher levels of cAMP and and leads to less activation of platelets, not as good by itself but combined with asparin
name some P2Y12 antagonists
clopidogrel and prasurgrel irreversible inhibitors and are prodrugs that need to be metabolized ticagrelor is reversible and does not need to be metabolized.
