I have been using methadone now for three years due to chronic pain from ten shoulder operations. Methadone provides great relief for my particular situation. I felt it necessary to share with those contemplating methadone use some pro's and con's from my personal experience. As I said above, a pro would definitely be the relief that I get from my chronic pain condition; It has absolutely improved my quality of life since the surgeries. Another positive thing I have experienced is that my tolerance has not gone up with methadone, whereas with oxycodone I had my dosage adjusted frequently. The biggest concern and con that I see regarding methadone treatment is the long term effect it can potentially have on your heart. It can cause a certain type of arrhythmia that once you get it, you have it for the rest of your life. The other things I would say are cons and certainly could be person specific is for me the way methadone has changed my personality. I went from being a highly motivated person to now suffering with bouts of depression and an overall lack of energy. My advice is to really be sure of your reason for taking it and too make sure you have someone who can provide some accountability to lessen the potential for abuse. A really good documentary concerning methadone use is called Methadonia. It does a pretty good job of giving a clear picture of pro's and con's of the drug.