You could also probably use those caffeine free energy drinks that are just liquid B vitamins in a little one shot bottle. I often see them at truck stops. Plus drink one glass of water per little bottle of B vitamins you drink, to prevent dehydration from excess drinking.

I just think of the caffeine, taurine, & ginseng as a bonus. 🙂

But you're right, not everyone can drink caffeine & then sleep... that is highly genetic... & it is in my genes. My mom drank coffee all day & night. She could have coffee at 9pm & go to sleep an hour later... & actually sleep. Snore, even.🙂