Is that like injectable meth? I wouldn't have a CLUE where to get that ****, but I'm interested none-the-less! I'd assume it would be similar effects, but going off of pretty much any other drug's timeline of effects based on route of administration, usually injecting is the fastest acting/shortest duration/hardest "punch", followed by snorting, inhalation, rectal, and then oral. Obviously not all drugs can be administered in all of these routes, but I would assume injectable ephedrine would fit the bill for fastest acting/shortest duration/hardest "punch", most likely requiring frequent, low dose injections for the same effects due to drug clearance timing.