Anticoagulants Flashcards
What is the mechanism of action of Warfarin?
It prevents gamma-carboxylation of factors II, VII, IX, X. It prolongs the prothrombin time
It also inhibits protein C and S
Why is LMW Heparin used till the INR is >2 for 2 days when Warfarin is prescribed?
Because Warfarin inhibits protein S and C which can cause a pro-coagulant state
What are the interactions of Warfarin?
Interacts with P450 and alcohol
What are the side effects of Warfarin?
It’s tetragenic so not used during pregnancy, significant haemorrhagic risk. Minor bleeding, skin necrosis, alopecia
How can Warfarin be reversed?
Using IV Vitamin K
How would a life-threatening bleed be treated when someone is on Warfarin?
Give activated prothrombin complex containing factors II, VII, IX, X. Fresh frozen plasma can also be used
What is the mechanism of action of Heparin?
It’s a mucopolysaccharide that potentiates anti-thrombin. It irreversibly inactivates factors IIa and Xa
How is unfractionated heparin administered?
IV infusion
How is LMW heparin administered?
Subcutaneous injections
How can unfractionated heparin be reveresed?
Partially reversed using protamine sulphate
What is the dose of LMW heparin dependent on?
Weight
Which type of heparin is more used because of convenience?
LMW Heparin because it is given by injection and not IV. It doesn’t need to be monitored either
Which type of heparin can be used with renal failure?
Unfractionated heparin
Tinzaparin, Enoxaparin, and Dalteparin are type of which drug?
LMW heparin
What type of drug is Dabigatron and how does it work?
Its a novel oral anti-coagulant (NOAC) what directly inhibits thrombin (IIa). Can’t be used with renal failure
What type of drug is Rivaroxiban and how does it work?
Its a novel oral anti-coagulant (NOAC) that directly inhibits factor Xa
What type of drug is Argatroban and how does it work?
Its an anti-coagulant that directly inhibits thrombin. It can be used with renal failure
When would the drug Apixaban be used?
As an alternative to Rivaroxaban
What is the mechanism of action of aspirin?
COX inhibitor
What is the mechanism of action of Clopidogrel?
ADP receptor blocker
What is the mechanism of action of Dipyridamole?
Inhibits phosphodiesterase
What is the mechanism of action of Prostocyclin?
Stimulates adenylyl cyclase
What is the mechanism of action of Abcixmab?
A Glycoprotein IIb/IIIa inhibitor. It’s a monoclonal antibody
What is the mechanism of action of Eptifibtide?
A Glycoprotein IIb/IIIa inhibitor. It’s a snake venom derivitive
What is the mechanism of action of Tirofiban?
A Glycoprotein IIb/IIIa inhibitor. It blocks platelet aggregation
