Anticoagulant drugs Flashcards
Indications for anticoagulant drugs (2)
Venous thrombosis
Atrial fibrillation
How does heparin work?
Potentiates anti-thrombin binding
What are the two types of heparin? What is the difference between these?
Unfractioned (“standard”) heparin
Low molecular weight heparin.
LMWH only inhibits Factor Xa
How is heparin monitored?
a) unfractionated
b) LMWH
a) APTT
b) anti-factor Xa assay, although routine monitoring not required
Complications of heparin therapy (3)
Bleeding
Heparin induced thrombocytopenia
Osteoporosis with long-term use
How can heparin be reversed? (2)
Stop administration
In severe bleeding give protamine sulphate (only gives partial reversal for LMWH)
Complications associated with heparin (3)
Bleeding
Heparin-induced thrombocytopenia
Long term use- osteoporosis
Reduced Vitamin K is required for the carboxylation of which clotting factors?
II (prothrombin), VII, IX, X
How does warfarin work?
Inhibits the reduction of vitamin K, stopping it from acting as a co-factor in the carboxylation of the clotting factors
INR is analogous to which other measure of coagulation?
Prothrombin time
Potentiators of warfarin (4)
Liver disease (reduced metabolism)
P450 enzyme inhibitors e.g. amiodarone
Cranberry juice
NSAIDs
Side-effects of warfarin (3)
Haemorrhage
Teratogenic
Temporary pro-coagulant state (reduced protein C synthesis)
How is the temporary pro-coagulant state in warfarin managed?
Concurrent heparin
How is warfarin reversed?
Oral vitamin K Clotting factors (FFP)
What does dabigatran inhibit?
Thrombin
