Final answer:
Feverfew can interact with anticoagulant medications like warfarin, increasing the risk of bleeding in patients. Close monitoring is recommended for patients taking both.
Step-by-step explanation:
The nurse should identify that anticoagulant medications, such as warfarin, interact with feverfew. Feverfew can increase the risk of bleeding, especially when taken with other drugs that inhibit blood clotting. It is important for healthcare professionals to monitor patients taking both feverfew and anticoagulants closely for signs of increased bleeding.