Yeah it called precipitated withdraw and occurs when a person takes bupronorphine too soon after their last dose (incidentally it has nothing to do with the naloxone in suboxone as this is inactive when taken sublingualy. During my recent methadone detox, after about 2-3 gweeks in I was suffering really badly and was offered low dose subs (4-8mg) from my local DSP which my gp referred me to. I was suffering so much that I cracked and accepted it but only stayed with it for 3 days as I realised it was a mistake I for me personally as I wanted to be drug free completely. On the fourth day I just didn't turn up for my titration appointment and have never been back. Obviously if I had tried to switch to subutex while still on 180mg of methadone it would have led to precipitated withdraw even after a day or two off but the 2 1/2 weeks I had refrained from taking my methadone prevented that.
While I didn't really give subutex a sufficient try to evaluate it properly I just knew it was a mistake to go down that route when I wanted to be clean. However the first 2-3weeks of acute withdrawl were stupidly tough..... Even tougher was the decision to not go with the subutex and resume those hideous withdrawals which continued for another couple of months.
I honestly think if you wanted to torture somene to get Information from them (a la the CIA or whoever) then getting them dependent on a very high dose of methadone then cutting them off overnight would be very effective as after a couple of weeks they'd tell you anything you wanted to know...... It really is that bad