Effect of beta blocker versus alpha combined alpha and beta blocker on blood pressure response under static exercise and cold pressor test

ABSTRACT

The effect of a single oral dose of beta-1 blocker [Metoprolol] versus combined alpha- and beta-blocker [Labetalol] was evaluated in two groups of patients Control [C] normotensive and hypertensive [H] groups with mild to moderate elevation of blood pressure. Each group consisted of 10 subjects. The study comprised monitoring the heart rate [HR] and blood pressure [BP] response to two tests Hand grip test [HCT] and cold pressor test [CPT]. These tests were performed before and after the drugs on separate sittings. The BP and HR response to HGT before administration of drugs was linear for the two groups, while the CPT showed insignificant rise of HR. The results at rest before and after medications in both groups showed a decrease in HR and BP. It was statistically insignificant in C group only after Labetalol used. In C group Metoprolol was more effective in lowering the pressor response than Labetalol, while in the H group Labetalol was potent in reducing BP, specially during CPT