-
what 6 things play a role in the "equilibrum" that normally prevents us from clotting up
- cAMP
- ADP
- ATP
- serotonin
- prostaglandins
- calcium
-
what is the integrin receptor for antiplatelets
glycoprotein IIb/IIIa
-
inhibition by reversibly binding of P2Y12
metabolized by CYP3A4 to an active metabolite
bleeding risk - intrcranial hemorrhage
alternate to thienopyridines
platelet function recovers twice as fast
brilinta (ticagrelor)
-
glycoasaminoglycan
ind - thrombosis/embolism, DIC, DVT, prophylactic clot formatin
binds to antithrombin III which then inhibits factor Xa
unfractionated heparin
-
2 most common clinical side effects of unfractionated heparin
heparin induced thrombocytopenia
-
a 50% drop in platelet count or less than 100,000 platelets per mL
thrombocytopenia
-
time to onset of heparin induced cytopenia is a function of exposre history - describe the 2
- previous exposure - platelet count can dive in hours
- first exposure - platelet count drops in 5-100 days
-
is the risk of thrombocytopenia greater with unfractionated heparin or low-molecular weight heparin
unfractionated
-
LMW heparin
prophylaxis of cancer-associated venous thromboembolism
dalteparin sodium - fragmin
-
LMW heparin
less thrombin activity with potent factor Xa inhibition
enoxaparin sodium - lovenox
-
Not a LMWH - synthetic
binds to AT III then inhibits selectively only factor Xa
2.5mg/day hip or knee replacement
fondaparinux sodium - arixtra
-
4 advantages of LMWH over unfractionated heparins
- can be self administered by the patient in an outpatient setting at home or by a home health care nurse
- improved control of bioavailability
- more selective for factor Xa
- less probability of thrombocytpenia
-
how do you reverse the anticoagulatory effect of heparin
protamine sulfate
-
poly-cation amine rich in arginine groups isolated from fish
derived from SAM
protamine sulfate
-
reverses anticoagulatory effect of heparin without some of the side effects
PEG-modified protamine
-
irreversible thrombin inhibitor
recombinant hirudin protein
gender difference issue with drug exposure
overdosage - whole blood replacement or thrombi
lepirudin - refludan
-
reversible thrombin inhibitor
used for acute coronary syndrome, unstable angina undergoing PCTA
bivalirudin - angiomax
-
human derived thrombin used topically in surgery
evithrom
-
irreversible thrombin inhibitor
used for DVT prophylaxis in elective hip replacement therapy
IV - caution in patients receiving epidural or spinal anesthisia - hematomas possible
desirudin - iprivask
-
reversible thrombin inhibitor
free and clot associated inhibitor
IV anticoagulant for HIT
argatroban - acova
-
reversible thrombin inhibitor
oral - in patients with non-valvular atrial fibrillation
dispense and store in the original bottle only
6- day shelf life once opened - moisture
no known antidote
dabigatran etexilate - pradaxa
-
treats chronic idiopathic thrombocytopenia
oral - acts at the bone marrow level
may cause hepatotoxicity
eltrombopag - promacta
-
vitamin K reductase inhibitor
prophylaxis for venous thrombosis, PE, Afib
dosage must be individualized
monitor INR
petechiae
do not switch brands
protein displacement is a major cause of drug interactions
warfarin sodium - coumadin
-
5 times more potent form of warfarin
S
-
which enatiomer of warfarin is metabolized by CYP3A4
what is its T 1/2
-
which enantiomer of warfarin is metabolized by CYP2C9
what is its half life
-
a single nucleotide polymorphism of what gene has been associated with lower dose requirements for warfarin
- VKORC1
- 30% variance alone
- 40% variance with CYP2C9 genes
- 55% variance with CYP2C9 genes, age,height,body weight, interactind drugs
-
this causes an interaction with warfarin
INR's can increae by up to 50
flavinoids inhibit CYP2C9
cranberry juice
-
this interacts with warfarin by inducing CYP2C9
american ginseng
-
vitamin K reductase inhibitor reserved for patients that can not tolerate coumarin type drugs
anisindione - miradon
-
factor Xa inhibitor
pure S enantiomer
substrate for CYP3A4/3A5
possible spinal and epidural hematoma
rivaroxaban - xarelto
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