Hey there guys. You have a bigger issue at hand here besides just coming down effectively. I think you know that though. Getting past the comedown is arguably much, much easier than the long process of not pick the Methamphetamine back up. You know how this goes; you get higher than you wanted to be, get disgusted, sleep for a few days and swear you'll never use Meth again because of how totally dark and miserable you feel. Then, once the sun comes up after a few days and you start to feel human again, the cravings hit. You need to have a game plan as a partnership for what you're going to do to get past this. I highly recommend you guys get some kind of outside support.
It is really easy to relapse when it's just between you and the drugs. When there is nobody keeping you honest, caring about if you fuck up, or better yet, when there is nobody who is proud of you for doing better, staying clean is just exponentially harder. I think you guys should commit to not using this shit anymore and enlist as much help as you can get to help motivate you through the hard parts. I personally am partial to the 12-steps. I don't subscribe to 100% of the program. I definitely subscribe to honesty, fellowship with other addicts and depending upon one another for strength. I'm Jewish and I've never seen anything truly "religious" about AA when you actually look closely. My point is, Methamphetamine is not easy to kick and keep it kicked. Don't waste time by fucking up over and over if you don't have to. It is different for everyone, but 12-step meetings are happening every second of every day and all you need is an internet connection. I go to at least 5 meetings a week, usually 2 in person.
If it weren't for my program, this downturn that has recently affected my life likely would have catalyzed a spiral back into addiction that would've ended with me ether overdosing, freezing to death anonymously or committing suicide, so I don't ever miss a chance to share it with others. I will add, I am extremely cynical and anti-organized religion, so if I can tolerate it, anyone can.
As far as your pharmacological issues:
These 7-Hydroxymitragynine products exert their effects through regular old Opioid agonism. If you are dependent upon Buprenorphine, than a significant portion of the 7OH is going to be blocked by the Bupenorphine. Being that this stuff is typically quite expensive, it's not really rational or cost-effective to buy the quantity of the stuff that would be required to end a Methamphetamine binge.
If you are needing sedation, you would be much better off acquiring something like a Benzodiazepine. If you are already taking Buprenorphine, it should only take a relatively small quantity of a given Benzodiazepine to put you to sleep. As a disclaimer, I have to mention that the combination of Opioids and Benzodiazepines is inherently dangerous due to the synergistic effects of the two when combined. Do your research, ask questions and be responsible. Let me know if there is anything we can do to help.
