A nurse is caring for a patient who is taking warfarin (Coumadin). Which of the following laboratory values should the nurse monitor regularly?

Warfarin (Coumadin) is an anticoagulant that works by inhibiting the synthesis of vitamin K-dependent clotting factors. Vitamin K is found in foods such as green leafy vegetables, broccoli, liver, and soybeans.Eating foods that are high in vitamin K can decrease the effectiveness of warfarin and increase the risk of blood clots.

Choice B is wrong because warfarin can be taken with or without food.

Taking the medication with food does not affect its absorption or action.

Choice C is wrong because stopping warfarin abruptly can increase the risk of thromboembolism.

If the patient experiences bleeding, they should notify their health care provider and follow their instructions.

They may need to adjust their dose or switch to another medication.

Choice D is wrong because aspirin is also an anticoagulant that inhibits platelet aggregation.

Taking aspirin with warfarin can increase the risk of bleeding and bruising.

The patient should avoid taking aspirin or other nonsteroidal anti-inflammatory drugs (NSAIDs) unless prescribed by their health care provider.

The patient who is taking warfarin should also have regular blood tests to monitor their international normalized ratio (INR), which measures how long it takes for their blood to clot.The target INR range for most patients is 2 to 3.

The patient should report any signs of bleeding, such as nosebleeds, gum bleeding, blood in urine or stool, or prolonged bleeding from cuts or wounds.

They should also report any signs of thrombosis, such as chest pain, shortness of breath, leg pain or swelling, or stroke symptoms.They should wear a medical alert bracelet or carry a card that identifies them as taking warfarin.

This statement indicates a need for further teaching because taking an antacid can interfere with the absorption of warfarin and affect its effectiveness. The client should not self-medicate with any over-the-counter drugs without consulting their healthcare provider first.

Choice A is wrong because reporting black tarry stools and abdominal pain to the healthcare provider immediately is the appropriate action.These symptoms may indicate gastrointestinal bleeding, which is a serious adverse effect of warfarin.

Choice B is wrong because stopping the medication if these symptoms persist is not advisable.Warfarin should not be discontinued abruptly without medical supervision, as this can increase the risk of thrombosis.

Choice D is wrong because increasing the intake of green leafy vegetables is not harmful.

Green leafy vegetables are rich in vitamin K, which is the antidote for warfarin overdose.However, the client should maintain a consistent intake of vitamin K and avoid sudden changes in their diet.