Mrs D.,
Your warning made the med sound like the drug from He11!
Methadone, after a careful heart check-up,
can be a very effective pain killer in the proper dosages.
My wife headed a methadone clinic for drug addicts for many years
and the onus of the med being only useful for drug addiction treatment is strong.
Many docs shy from it like a plague, but it can be very useful,
with only minor needs for watchfulness.
As with all meds, we have to consider not only side effects, but interactions with other meds or supplements. Methadone has proven to be an inexpensive and valuable tool in helping with PN pain.