is a very dangerous drug , it is often abused by heroin
addicts , for it has similar addictive property's through binding to the same receptor sights. You make no mention of the possible cause and subsequent diagnosis for you back pain
. I would strongly suggest that if it is not clear what the cause is you see an orthopedic surgeon whom can make a diagnosis . There are many other treatment options that are safe , however the treatment plan depends on the causation . I strongly advise you to withdraw from the methadone under professional supervision as it might be responsible for all the above mentioned side effects.