Haha! Junkies will never stop slamming once they start. Sure, the might take a couple of weeks off from the needle, squirting it up their asses instead, but they'll miss the intensity and efficiency of shooting it straight into their blood stream, and be right back to the jab, maybe(hopefully) doubling down to make up for the fixes that were lacking. Nothing is better than injecting a drug into a vein, if the ass-enama method was better, you can bet your ass that's how hospitals would be medicating people.