system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: If I drink half of a Five Hour Energy, will I have half the energy for five hours or the "full" amount of energy for 2.5 hours?
gpt
There are multiple active ingredients in the stuff. Each of them has a curve that initially goes up relatively quickly and then fades slowly as your body processes it.

If you take half, the strength of those curves cut, but they are not squashed in the time dimension.

That said, it takes a lot longer than 5 hours for it to be 100% out of your system. The "effectiveness" ends when the strength falls below a certain threshold. With a lower dose, that would happen sooner.

So, it would be weaker at its peak _and_ not last as long.