Bup might affect your cannabis tolerance too. A friend was on high strength patches and could tolerate boatloads. Her doctor then prescribed tapentadol on top of it and an SSRI causing serotonin syndrome and now they won't treat her pain at all. Once off patches, she had a much lower tolerance.
Yeah, there is definitely going to be a transition phase of figuring out how it interacts with other meds I'm on. I'm hoping it's going to allow me to come off most of them in the end though. Tapentadol is on my 'do not touch' list as I lasted about 48 hours on it and it made me extremely suicidal
Got to love the NHS - almost kills the person by misprescribing a high risk drug combo and then withdraws all treatment permanently because of their mistakes. (Always check for interactions on the BNF and on US based interaction checkers - they seem to miss most here, but that was on BNF in red.)