Test 3 Warfarin

Question 1

warfarin

Answer 1

• vitamin K antagonist

* inhibits enzymes which reduce oxidized vitamin K

Question 2

Describe the narrow therapeutic index associated with warfarin

Answer 2

a 5 – 10% change in the weekly warfarin dosage can significantly change the INR

Question 3

warfarin enantionmers

Answer 3

• S enantionmer most effective

- there is also an R enantionmer

Question 4

recommended vitamin K intake for adult men

Answer 4

120 mcg

Question 5

recommended vitamin K intake for adult women

Answer 5

90 mcg

Question 6

examples of vegetables that have vitamin k

Answer 6

spinach, turnip greens, mustard greens, brussel sprouts, broccoli, lettuce, cabbage, carrots, corn, green beans

Question 7

What other consumption product also has vitamin K?

Answer 7

• enteral nutrition
• vitamin supplements
• liver
• green teas

Question 8

How do you measure the therapeutic effect of warfarin?

Answer 8

PT / INR

Question 9

What are the targets for warfarin?

Answer 9

• low intensity target is 2.5 (goal 2 - 3)

- high intensity target is 3.0 (goal 2.5 - 3.5)

Question 10

What happens if CYP34A is inhibited?

Answer 10

will change your INR 10% -> 10% dosage change

Question 11

Which medications can inhibit metabolism?

Answer 11

– Lovastatin and simvastatin 
– Gemfibrozil and fenofibrate 
– Prilosec (omeprazole) 
– Nexium (esomeprazole) 
– Prevacid (lansoprazole) 
– Protonix (pantoprazole) 
– Aciphex (rabeprazole)

Question 12

Drug food interaction: increase INR

Answer 12

- by inhibiting metabolism 
• cranberry, cranberry products 
• grapefruit, grapefruit products 
• decrease in dietary vitamin K 
• acute ingestion of ethanol

Question 13

Drug food interaction: decrease INR

Answer 13

• increase in dietary vitamin K
• supplement drinks (e.g. Slimfast, Boost, Ensure)
• ingestion of green tea

Question 14

BAM IF

Answer 14

• Bactrim
• Amiodarone
• Metronidazole
• Itraconazole
• Fluconazole
• inhibit 2C9 (which metabolizes S isomer)