Anticoagulants Flashcards
Name the different types of anticoagulants
Warfarin
Heparin
Direct oral anticoagulants
Anti-platelet drugs
What are anticoagulants used for?
DVT
PE
AF
Acute coronary syndromes (angina etc)
What is warfarin used for?
DVT PE AF Prosthetic valves Recurrent thrombosis
What is the action of warfarin?
Inhibits vit K dependent clotting factors (9,10,protein C+S)
Why does heparin need to be given initially when taking warfarin?
Warfarin has a slow onset of action
What other drugs/substances should be avoided when on warfarin and why?
NSAIDS and aspirin: Increased risk of bleeding
Alcohol: high levels acts as an enzyme inhibitor
Antiepileptics: inhibit it (with the exception of sodium valporate)
What’s given during pregnancy instead of warfarin?
Heparin
What are the ADRs of warfarin?
Bleeding or bruising in brain
GI disturbances
Epistaxis
Teratogenic
What are the uses of heparin?
Prevention of thromboembolism
Used peri-operatively (quick onset and offset)
What is the action of LMW heparin?
Binds to and activates antithrombin 3
This deactivated Factor 10a
How is heparin administered?
LMW heparin- sub cutaneous
Unfractionated- IV
Not oral- poor GI absorption
What are the ADRs of heparin?
Bruising
Bleeding
Thrombocytopenia
Osteoporosis (chronic use of drug)
What drug can be used to reverse heparin? Why?
Protamine (sulphate)
Dissociated heparin from antithrombin 3 and bind to it irreversibly.
Used if a pt is actively bleeding
What is the action of unfractionated heparin?
Binds to and inactivates 2a (thrombin)
In terms of monitoring, what is the difference between LMW and unfractionated heparin?
LMW- no monitoring required
Unfractionated- monitor APTT
