Methadone
"I use to be on 800mg of morphine instant release. Withdrawal was immediate (4-8 hours) if I ran out or missed my doses, usually it was the latter. As it was easy to increase dose without major side effects, I was always taking more rather then less and having to lie to my doctor about why I was always early. Finally went to detox 3 times and then started methadone. My highest dose 120mg, now 105mg, which works well for my pain."