For a patient with Stage II hypertension and second-degree heart block, which medication should be avoided?

In a patient with Stage II hypertension and second-degree heart block, the medication that should be avoided is a calcium channel blocker. This is primarily because certain calcium channel blockers can have negative effects on cardiac conduction, which may exacerbate the heart block. Specifically, non-dihydropyridine calcium channel blockers, such as verapamil and diltiazem, can further depress heart rate and conduction, leading to potential complications in patients with existing conduction issues like a second-degree heart block.

In contrast, ACE inhibitors, angiotensin receptor blockers, and diuretics are generally safer options for managing hypertension in this patient population. These medications do not significantly impact cardiac conduction and can effectively manage blood pressure without worsening the block. Therefore, while treating a patient with hypertension and a conduction disorder, it is crucial to select antihypertensive agents that maintain cardiac stability, making calcium channel blockers a concern in this scenario.