This really depends primarily on whether or not you are taking actual yohimbe or just the bark extract found in most of your health supplements. Even the more expensive 'male performance improvement' supplements that advertise yohimbine hcl are not delivering the actual hydrochloride. So lets say you're a weightlifter and you're taking some of the trib/ymb supps...just go ahead with your stim. The bark extract, usually 2% alkaloids, just isn't strong enough to contraindicate with most stimulants, including meth. Or lets say you're a guy who dopped some Extenze for a session with his lady - here again, just go ahead = after a couple hours you're almost down to baseline in that regard. Point of fact, I take a trb/ymb supp CONCURRENT with cocaine or meth or whatever stim I happen to be on if I can't get it up...aside from a temporary increase in heartrate (and obviously BP) everthangz everythang, y'know? Now, having said that I notice that you specifed a dose of 12*2 - which tells me you might have the 2mg yhm-hcl tabs - another animal entirely. However, the half-life of ymb is very short as you already discovered, and the metabolites are not the cause for significant concern - except in the case of taking DXM - BAD IDEA with ymb hcl! This can lead to horrific effects - as I discovered a decade ago when I took a dose of DXM when I was taking a workout supplement that had a strong dose of ymb (Thermorexin) as well as a straight ymb supp - I had a very severe case of serotonin storm that I was quite fortunate to survive (likely from a great deal of conditioning and earlier errors with MDMA and DXM, so forth...); anyway, 3MMC is the ticket here just to be sure, hold off on the ^A and be VERY careful with the GHB as an adjunt (as I am sure you already know)...I also did GHB with about everything for nearly a decade and if you research my posts back about five years you'll find loads of sneaky contra=indications I discovered, as well as the strategies for reversing some of them. Anyway, 24 hours is more than enough my friend. Be safe and have fun!