A client admitted on warfarin therapy has an INR of 1.2. What action should the nurse take first?

A client admitted on warfarin therapy has an INR of 1.2. What action should the nurse take first?

• A. Administer phytonadione (AquaMEPHYTON) to the client?
• B. Withhold the client's next dose of warfarin (Coumadin)
• C. Encourage the client to increase intake of iron-rich foods
• D. Determine if the client is taking the medication as prescribed

Answer: (D)

When a client on warfarin has an INR below the therapeutic range, the first step is to verify that the patient is taking the medication exactly as prescribed. Nonadherence is a common reason for a subtherapeutic INR, and confirming adherence guides the next actions—whether that means re-educating the patient, adjusting the dose, or evaluating for factors like diet or drug interactions that can lower INR. Administering vitamin K would reverse anticoagulation and is reserved for an elevated INR or bleeding risk, not a low INR. Withholding the next warfarin dose would worsen under-anticoagulation and isn’t addressing why the INR is low. Iron-rich foods don’t influence warfarin to raise the INR, whereas factors like vitamin K intake or concurrent medications can. So the priority is to confirm adherence and then assess and address any factors that could be reducing the effect of warfarin before making dose changes.

When a client on warfarin has an INR below the therapeutic range, the first step is to verify that the patient is taking the medication exactly as prescribed. Nonadherence is a common reason for a subtherapeutic INR, and confirming adherence guides the next actions—whether that means re-educating the patient, adjusting the dose, or evaluating for factors like diet or drug interactions that can lower INR.

Administering vitamin K would reverse anticoagulation and is reserved for an elevated INR or bleeding risk, not a low INR. Withholding the next warfarin dose would worsen under-anticoagulation and isn’t addressing why the INR is low. Iron-rich foods don’t influence warfarin to raise the INR, whereas factors like vitamin K intake or concurrent medications can. So the priority is to confirm adherence and then assess and address any factors that could be reducing the effect of warfarin before making dose changes.