I meant "stimulant" in the context of traditional dopamine reuptake inhibitors and releasing agents like amphetamine and ritalin which are almost incomparable to less controlled or uncontrolled compounds like modafinil, ephedrine, and caffeine. Even a high dose of caffeine will not produce effects anything like amphetamine. The mechanism of action between amphetamine and caffeine are fundamentally different rather than being a matter of strength. It's unfortunate and misleading that the word stimulant is used for both categories.
Modafinil is a dopamine reuptake inhibitor though, it's just an atypical one. I can't take especially high therapeutic doses of either it or Vyvanse without getting similar physical anxiety.
I assume the reason it's not highly controlled in the US is that it's atypical enough to not be addictive (not that I've ever found Vyvanse to be addictive), but it is controlled in Japan and Russia and it's definitely possible to abuse it. People need their sleep even if it can keep it away for a day.
