Final answer:
C. Digoxin is NOT an antihypertensive drug while both A. enalapril and B. clonidine are used to treat hypertension. Enalapril is an ACE inhibitor and clonidine is an alpha-2 adrenergic agonist, whereas digoxin treats heart failure and atrial fibrillation, not hypertension.
Step-by-step explanation:
To answer the question of which of the following is NOT an antihypertensive drug—A. enalapril, B. clonidine, or C. digoxin—the correct answer is C. digoxin. Enalapril and clonidine are indeed antihypertensive medications. Enalapril belongs to a class of drugs known as angiotensin-converting enzyme (ACE) inhibitors, which include others like benazepril and lisinopril. Clonidine, on the other hand, is an alpha-2 adrenergic agonist, which lowers blood pressure by reducing the sympathetic nervous system activity.
On the contrary, digoxin is a cardiac glycoside, primarily used to treat heart failure and atrial fibrillation, a type of irregular heartbeat. It is not used as an antihypertensive therapy. These antihypertensive drugs function to directly lower blood pressure, while digoxin works by increasing the efficiency of the heart and controlling its rate and rhythm.