Yeah, Bupe has a ridiculously long half life. It binds to your receptors for an ungodly long time. I hate it when I run out of Bupe, have other opiates, but can't feel them and help the bupe withdrawal because it's still lingering in my system. Again, I personally like to take Tramadol while going threw Bupe withdrawal. Tramadol does wonders for this. I have found though, to be honest, if I'm on my, lets say 1st or 2nd day of bupe withdrawal, other opiates DO actually help warm me up a little, so it's not like they are totally blocked. I'll say it again, I'm a big advocate of Tramadol. Not just for bupe withdrawal, but even in conjuction with it. People frown upon Tramadol often thinking it's worthless(all because of how it was first marketed as non addictive and non narcotic), but the truth is, Tramadol can be a great pain reliever while producing a noticably high increase in mood.