They don't have a clue how this drug works. It appears to have similar actions to methamphetamine, but does not have a related structure. It also affects the adenosine receptors, which caffeine does as well. Adenosine has a calming effect on the body. So blocking these receptors prevents adenosine from calming us.
A few suggestions are pollen if you are not allergic. The high B vitamin content of pollen makes it a great energizer. Pollen also helps to strengthen the adrenals due to its high content of pantothenic acid.
The amino acid carnitine is also great for helping to increase energy. Carnitine helps to move fatty acids in to the mitochondria to be used as fuel.
Bitter orange is a mild stimulant, but whether or not it would be too much for your adrenals is hard to say. It is very mild, but it will still depend on how bad your adrenals are and how much you use.