What is the main MOA of Clonidine (Catapres)?

What is the main MOA of Clonidine (Catapres)?

• A. CNS Alpha 2 agonist
• B. Beta blocker
• C. Alpha 1 agonist
• D. Diuretic effect

Answer: (A)

Clonidine works mainly by activating alpha-2 adrenergic receptors in the central nervous system, especially in the brainstem. This activation dampens sympathetic outflow from the CNS, reducing norepinephrine release onto the heart and blood vessels. The result is lower peripheral vascular resistance and blood pressure, often with a slower heart rate due to diminished sympathetic drive. This central action distinguishes it from a beta blocker (which blocks beta receptors on the heart), an alpha-1 agonist (which would cause vasoconstriction), or a diuretic (which lowers blood pressure by reducing volume).

Clonidine works mainly by activating alpha-2 adrenergic receptors in the central nervous system, especially in the brainstem. This activation dampens sympathetic outflow from the CNS, reducing norepinephrine release onto the heart and blood vessels. The result is lower peripheral vascular resistance and blood pressure, often with a slower heart rate due to diminished sympathetic drive. This central action distinguishes it from a beta blocker (which blocks beta receptors on the heart), an alpha-1 agonist (which would cause vasoconstriction), or a diuretic (which lowers blood pressure by reducing volume).