Opiate Dependence
"People, if you are switching from methadone or buprenorphine  (Suboxone) , do NOT get the shot right away. Both methadone and buprenorphine are long acting opiates. When a medical professional tells you that you need to stay clean for 5-7 days, they are speaking of short acting opiates. Heroin, OC, OP, OHC, and I&#039;m sure the other codeine derivatives have a much shorter half-life (a measure of how long they stay in your body) than do methadone and buprenorphine. 

If you are trying to switch from one of the long acting opiates to the naltrexone shot, personally I would switch to a shorter acting opiate for two week, then stay clean off the for 4-5 days, and then get the shot. I understand this may not sit well with some people."