رجل عمره ٧٠ سنة عنده ذبحة صدرية مستقرة، يستخدم لصقة نيتروجليسرين ويتركها على جلده ٢٤ ساعة كل يوم من شهرين. يقول إن نوبات الألم مع المشي رجعت تزيد وكأن اللصقة صارت أقل فائدة. ضغطه ١٢٨/٧٤. أي تعليمات تعالج هذه المشكلة؟

A 70-year-old man with stable angina has worn a nitroglycerin patch 24 hours a day for two months. He says angina with walking is increasing again, as if the patch works less well. BP 128/74. Which instruction addresses this problem?

1. Cut the patch in half and place the pieces on the chest and arm
2. Apply two patches instead of one at the same site to raise the dose
3. Remove the patch for 10–12 hours each day as prescribed, usually overnight
4. Move the patch every 6 hours without taking it off overnight

Answer: C) Remove the patch for 10–12 hours each day as prescribed, usually overnight. Continuous nitrate exposure causes tolerance. The fix is a daily nitrate-free interval as prescribed. Doubling the dose or cutting the patch is wrong.