護理師正給予華法林（warfarin）。病人詢問哪些食物會與藥物產生交互作用。護理師應建議病人限制攝取下列哪些食物？
A nurse is administering warfarin. The client asks about foods that can interact with the medication. The nurse should advise the client to limit intake of which of the following foods?
- AApples蘋果
- BChicken雞肉
- CSpinach✓ 正解菠菜
- DOranges柳橙
華法林透過抑制維生素 K 依賴性凝血因子（II, VII, IX, X）的合成來發揮抗凝血作用。菠菜富含維生素 K，會抵消華法林的藥效。病人不需完全禁食菠菜，但需保持「攝取量穩定」，以避免藥物濃度波動導致 INR 不穩定。教育重點應在於限制大量攝取，並維持飲食的一致性，這是預防出血或血栓風險的關鍵衛教。
Warfarin exerts its anticoagulant effect by inhibiting the synthesis of vitamin K-dependent clotting factors (II, VII, IX, X). Spinach is rich in vitamin K and counteracts the effect of warfarin. The patient does not need to avoid spinach entirely but must keep intake consistent in order to prevent fluctuations in drug levels and an unstable INR. Education should emphasize avoiding large intake while maintaining dietary consistency; this is the key teaching point for preventing bleeding or thrombotic risk.