Bad Idea to take the suboxone untill your in pretty good withdrawl. Suboxone has naltraxone in it which is an opiet blocker. When dosing with suboxone after using methadone you need to wait as long as possible and make sure your into withdrawls pretty good because methadone has a really long half-life. If your dose with suboxone too soon it could send you into some pretty intense and uncomfortable precipitated withdrwals.
Actually Suboxone has naloxone, not naltrexone and it isn't the naloxone that blocks the effects of other opiates, its the buprenorphine. You shouldn't take the two together. The buprenorphine would block the effects of the methadone.
Mixing Suboxone and methadone is asking for trouble. It is advised to wait until the methadone has left your system (which is longer than 12 hours, think 48-72 hours) before taking Suboxone.
noooo DO NOT mix them unless you want to be thrown into WD. that is if you were already on methadone then took the suboxone without waiting the needed time...usually like 2 or 3 days. it takes a while for the methadone to clear out.
now if you took methadone while on suboxone it probably wouldnt do anything since the bupe is so strong.