deidara
Bluelighter
Well, the "high" would have to be similar, but the "rush" would most likely not be similar at all. In other words, an hour or so later after each drug had been administered, I would imagine that the effects and the feeling, the "high" each user feels, would be so similar as to be indistinguishable. In fact, I'm pretty sure that they've done studies on such a thing and this was their observation. that IV heroin users could not tell the difference between IV heroin and IV morphine.
I've had both IV many times and in my experience after the morphine rush is over, I don't get any type of high from it. After the heroin rush it leaves me with euphoria, warmth, and a nod if I'm lucky. Morphine for me is just a really intense pins and needles rush followed by absolutely nothing.