Which statement best reflects appropriate warfarin teaching?

• A. Stop the medication during illness
• B. Increase vitamin K intake to boost clotting
• C. Take at the same time each day
• D. Skip doses if you forget

Answer: (C)

Consistent dosing time helps maintain stable anticoagulation with warfarin. The medication has a narrow therapeutic window, so keeping the drug level steady by taking it at the same time every day reduces fluctuations in INR. When timing is regular, the body’s response stays more predictable, lowering the risk of bleeding from too much anticoagulation or clotting from too little.

Stopping the medication during illness can lead to loss of protection against clots and may require a provider’s guidance, since illness can also alter how the drug works. Increasing vitamin K intake would counteract warfarin’s effect, making it harder to achieve therapeutic anticoagulation. Skipping doses can cause gaps in protection and raise the risk of clot formation. If a dose is missed, follow clinician guidance rather than stopping or improvising doses.