Which of the following is a common contraindication to nitroglycerin administration?

• A. Systolic BP below the threshold or recent PDE inhibitors use.
• B. Allergy to aspirin.
• C. Chronic kidney disease.
• D. Asthma.

Answer: (A)

Nitroglycerin works by dilating veins and arteries, which lowers preload and afterload and can reduce blood pressure. The most important safety concern is avoiding inappropriate hypotension, especially when blood pressure is already low or when a patient has recently used a phosphodiesterase type 5 inhibitor (like sildenafil or tadalafil). That combination can cause a dangerous drop in blood pressure and impaired perfusion. So a criterion that mentions either systolic blood pressure below the threshold or recent PDE inhibitor use directly targets the major safety rules for nitroglycerin administration, making it the best choice. Other options like aspirin allergy, chronic kidney disease, or asthma do not constitute common contraindications to nitroglycerin in typical standing orders, though they may influence overall management in different ways.