Sorry for posting to this sort of old thread, but I have been reading up on Subs tonight, after having taken an 8mg filmstrip earlier today, and came upon this thread regarding kratom and "sub"sequent Suboxone use.
I'm afraid I can't give much of an answer to the OP's question, but I wanted to chime in with some general info on using kratom during, after, or in place of opiate use/addiction/dependence.
Some alkaloids in kratom are indeed mu-opioid receptor agonists, although as mentioned before the kratom leaf will never be as strong as morphine-based opiates (except maybe codeine or low dose hydrocodone). There are a couple of extracts, such as the above-mentioned Full Spectrum Tincture and another extract-enhanced powdered leaf product called Ultra Enhanced Indo, that are fairly strong. Most plain leaf and even extracts are however rather mild in comparison to morphine, oxy, hydro, and especially heroin.
People who are toleranced to opiates will likely require fairly large doses of kratom leaf in order to achieve the desired effect, if they are able to get it at all. If a person is opiate-naive, however, the effect would be similar to that of a low to moderate potency opiate, although qualitatively different. The euphoria and pain relief aspects are present, but not as extreme as with morphine-based opiates. Also, the withdrawal symptoms from kratom alone (it can cause them in some people, others do not get them even with heavy daily use) are far less severe.
When I quit methadone using kratom, I first tapered the methadone over months to the point where I was quite comfortable on 10-20mg/day. Then, I was able to switch painlessly to kratom using ~8g orally (don't make tea, swallow the powder whole) every 6-10 hrs. From this point, kratom can be tapered (much easier than tapering opiates) or used for maintenance, as well as for chronic pain, insomnia, and a whole slew of different purposes.
I personally find it to be a very beneficial herb for medicinal purposes, although not particularly recreational. Like I said, euphoria is present although not comparable to morphine-based compounds.
Also, I wanted to mention this... if you are getting your kratom leaf in gram bags, I assume they are coming from a head shop or legal-high type vendor. These are not the sorts of vendors I would ever buy kratom from, as it is likely overpriced, and low quality. You want a vendor that specializes in kratom. There is a lot of crap kratom out there these days, which has been leading some people to think it doesn't work. Trust me, this shit saved my ass from OC/methadone addiction, it works!
As far as the OP's question, you are supposed to only take the Sub when you are in moderate withdrawals at least, or you can risk getting thrown into PW's. I've been through PW's, it's a bitch! If you're not sure that you're sick enough yet, wait 12 hours just to be safe. If you didn't even feel the kratom at all though, and you are already in severe withdrawals, you should be OK, but maybe wait a bit just in case.
