If caffeine works by blocking the receptors that make you feel tired, why does too much caffeine cause you to feel “wired”?

Question

Shouldn’t you just max out at feeling perfectly alert/rested?

In: Biology

Answer 1

Because caffeine has multiple effects on multiple systems. Blocking tiredness is just one of them. It is also a central nervous system stimulant that raises heart rate etc. It’s this effect that can take you to being “wired” above your baseline alertness level.