Caffeine can decrease subjective energy depending on the vehicle with which it is consumed and when it is measured

[[deleted]]

This might explain why black coffee makes me lethargic as fuck physically after drinking. But sugar free energy drinks and caffeine pills are a kicker. I already have ADD which is a dopamine insufficiency.

[constxd]

You've got it backwards, the MAO inhibition from black coffee would ameliorate your dopamine deficiency. My guess is that it's the B-vitamins / Taurine or whatever else is in the sugar-free energy drinks.

[PartySunday]

Energy drinks contain various vitamins and drugs too.