I injected quite a lot of it some time ago and I've just done it again. My conclusion is that it seems to resemble codeine in a way. It's definately more histaminergic than hydromorphone and there's no instant rush, it comes on slowly. I've got red streaks on the veins I injected into and a small rash around my wrists.
I wonder if the same happens with oxycodone? Sure they both hydrocodone and oxycodone can have a stronger affinity to opioid receptors than codeine but hydrocodone seems more of a prodrug. Is this the same for oxycodone injected i.v.?