Alot of energy drinks depend upon caffeine, which is not energy, it's a stimulant. Caffeine is there to give a stimulus to physical performance (sometime mental performance). But a stimulant can be a bad. Excessive stimulation due to caffeine can have a detrimental effect not only on physical performance, but also on aspects of metabolism that influence health (such as blood pressure and heart rate).
Charles, with your normal bp being that high, you should definitely stay away from heavily caffeinated drinks (or gums, or soaps).
Now if you're also drinking alcoholic beverages with the heavily laden caffeine products, then it can cause you to become dehydrated. Dehydration causes other problems, or magnifies those listed above, and could give you the opposite of what you're really wanting.
Dave
