Lecture 16- Anticoagulants Flashcards
What are 3 events that occur after injury?
- Vascular spasms –> platelets release serotonin, spasm, decrease blood loss
- Platelet plug
- Coagulation –> net like structure (fibrin) to seal opening of injury
Look at the coagulation cascade in the slides (slide 6)
What are anticoagulants?
do not dissolve clots already formed just PREVENT clots from becoming larger
treat primarily for thrombosis in veins
What do oral anticoagulants (specifically indirect thrombin inhibitors) produce a functional deficiency of?
vitamin K
What are the two groups that Indirect Thrombin Inhibitors fall into and what drug is most common to each group? (these are anticoagulants btw)
- Inhibitors of clotting factor synthesis –> Warfarin
- Inhibitors of Thrombin –> Heparin
What is Heparin used for?
activates antithrombin II –> blocks thrombin
–> activates factor Xa
What are the adverse effects of heparin and warafin?
hemorrhage
are older adults more susceptible to the effects of anticoagulants?
yes!
What is “Low Molecular Weight Heparin” (LMWH)?
- anticoagulant that is given by injection under the skin
- to prevent and treat venous thromboembolism
- inhibits Factor Xa and IIa
- cannot be given orrally
- safer!!
What is the name of an LMWH drug?
dalteparin
What is warfarin (aka rat poison)?
interferes with hepatic synthesis of vitamin K dependent clotting factors (II, VII, IX, X)
- for long term
- narrow therapeutic
- interacts with drugs and food
- NEEDS MONITORING
What are tips they give patients if taking Wafarfin?
- 5 days before dental procedure –> STOP TAKING IT
- supplments of vitamin K (like Kale) can potentiate or inhibit it!
What are Direct Thrombin Inhibitors (DTI)for anticogulants?
directly inhibit the enzyme of thrombin (factor IIa)
What are the 3 types of DTIs ?
- bivalent –> bind active site and exosite
- Univalent –> bind active site ONLY
- allosteric inhibitors
What are antiplatelet drugs used for?
prevent platelets from binding together –> clot formation!!!!
