Drums can be a very tiring instrument to play, and that's coming from someone who's never picked up a drum stick in their life. I've instead come to that conclusion after watching various drummers either live in a venue or on TV/online. Just watching them manically drum is tiring enough.
So, like all good rock musicians, or any musician really, it's no surprise that some of them must consume drugs. Not purely for recreational purposes you understand, but to aide in their efforts and also, according to this very funny sketch, to influence their style.
Jared Dines, a metal fan and musician, comedically runs through the various styles of drumming while under the influence of various drugs. And the similarities to some famous drummers is uncanny.
From the classic rock pick me up cocaine, to the wild fringes of hallucinogens, ecstasy, weed, even good old alcohol. Seeing the effect on their musical styles certainly rings true.
They're all there.
So now you know what signs to look for next time you see your favorite drummer letting rip on stage.