methadone is rarely given out as a maintenance script now more for detoxing & study's have shown long term use pain pets worse & duck being hooked on that for years!
Personally I think methadone should only be used as a quick detox it's brilliant if used properly a bitch if abused ' sadly us addict basically abuse everything including our selves!
my advice is cut down slowly I can't comment on the other drug but after a month or two of sleepless nights your sleep will come back & sleep better off that shit than you ever did on it!
good luck Stafe MarcVinal