How does warfarin exert its pharmacological effect (40% marks)? Write brief notes on the pharmacology of the agents that can be used to reverse the effects of warfarin (60% marks).
Warfarin is listed as a level 1 drug in the 2017 syllabus and as such a detailed knowledge of its mechanism of action would be expected from candidates sitting the exam. The reversal agents for warfarin are collectively classed as level 2 drugs and hence the knowledge required would be at a write short notes level. The following topics were expected: what drugs may be used, how they work, in what dose, any common side effects, why/when would one be used in preference to others etc. The use of reversal agents for warfarin is a common practice in ICU. Generally, answers demonstrated a lack of a precise and detailed knowledge with respect to warfarin’s mechanism of action and had a very superficial knowledge with incorrect facts regarding the reversal agents.
Mechanism of action:
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