Well I finally managed piss dirty again and got booted from my program. To be honest I hadn't been taking my bupe too often anyways. I got about a week's worth of oxy, and when it was gone, I did a quick sub taper. I am curious to see what kind of withdrawals I have, if any.
None of the ppl who used to be on here seem to be around anymore, but if anyone's interested, I'll keep you posted. If I can't stay somewhat clean, I may try methadone.
The ROA does affect bioavailability, and affects DURATION of effects, but it doesn't change the half life too much... To get really technical, it shortens it very slightly, but only because your body gets the bupe faster, so it starts breaking it down sooner. We're talking a matter of minutes though.
As far as bioavailabilities: obviously when you IV a drug, you are getting 100% of it into your system. Everything else is relative to that. When you take bupe sublingually, the bioavailability is only around 30%. So you are only getting a third of what you actually take. Nasal and rectal BA's are both around 50% for bupe.
Bupe is highly protein bound which is what makes the half life so long. Regardless of whether you shoot it, snort it, plug it, or take it sublingually, it will still bind to protein and the half life won't change by any significant amount.
Also, yes, the oral BA of bupe is only around 10%. So if you swallow it, you're barely getting any of it, only a tenth of what you would if you IV it or a third of what you would sublingually.