Final answer:
An anticoagulant, such as Coumadin, is used to interfere with the action of vitamin K, preventing blood clots in patients with atrial fibrillation and other cardiovascular conditions. These drugs work by inactivating clotting factors and are dosed carefully to avoid overdose, with pharmacogenomics aiding in personalized medication management.
Step-by-step explanation:
The substance that interferes with the action of vitamin K and is used for atrial fibrillation is an anticoagulant. Anticoagulants such as Coumadin (warfarin) help prevent clotting in patients with various forms of cardiovascular disease, including those who have had a heart attack, unstable angina, ischemic strokes, TIA, and who are experiencing atrial fibrillation. These medications work by inactivating clotting factors, such as factor X, which blocks the conversion of prothrombin (factor II) into thrombin, thereby preventing the formation of blood clots.
Vitamin K plays a crucial role in the blood clotting process by activating certain proteins that are essential for coagulation. In the case of anticoagulant therapy, pharmacogenomics can be employed to optimize dosing for individual patients, potentially reducing the risk of overdose especially in patients with varying liver functions, which affects the metabolism of medications.
Anticoagulants may prevent clots from becoming larger and causing more serious problems, making them a common prescription to prevent first or recurrent strokes. Pharmacogenomics can assist in managing Coumadin therapy by tailoring medication to an individual's genetic profile, which can influence how they metabolize the drug and their sensitivity to vitamin K.