Certified Diabetes Care and Education Specialist (CDCES) Practice Exam

Which patient would not be a candidate for a phosphodiesterase type 5 inhibitor such as sildenafil?

1. A man with stage 3 chronic kidney disease (CKD)

2. A man with moderate liver impairment

3. A man with mild ischemic heart disease who uses nitroglycerin spray prn for chest pain

4. All of the above

The correct answer is: A man with mild ischemic heart disease who uses nitroglycerin spray prn for chest pain

A phosphodiesterase type 5 (PDE5) inhibitor, such as sildenafil, is primarily used for the treatment of erectile dysfunction and certain types of pulmonary hypertension. However, there are specific contraindications regarding its use due to its vasodilatory effects and potential interactions with other medications. A man with mild ischemic heart disease who uses nitroglycerin spray as needed for chest pain presents a significant risk when considering the use of sildenafil. Both sildenafil and nitroglycerin act as vasodilators, and when used together, they can lead to severe hypotension (low blood pressure), which can be dangerous. This interaction forms the basis of the contraindication against prescribing PDE5 inhibitors to patients who are also using nitrates for heart conditions. Though patients with stage 3 chronic kidney disease and moderate liver impairment may require careful monitoring and potential dose adjustments, they are not outright contraindicated for sildenafil use. Therefore, they may still be candidates for treatment, depending on the specific circumstances and overall health status. In summary, the key reason the man with mild ischemic heart disease who uses nitroglycerin is not a candidate for sildenafil is due to the serious risk of significant drug interactions that could lead to harmful consequences.