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What is Which of the following drug reduces blood pressure primarily by directly decreasing heart rate alone? and explain in detail?
Ans. (A) Propranolol(Ref: Katzung 10/e p165, 169; KDT 8th/e p158)*Methyldopa is useful in the treatment of mild to moderately severe hypertension. It lowers blood pressure chiefly by reducing peripheral vascular resistance, with a variable reduction in heart rate and cardiac output.*Prazosin and nitroprusside are vasodilators and produce reflex tachycardia instead of causing bradycardia.*Propranolol is a non selective beta blocker and acts mainly by decreasing heart rate.