Hi...well vivitrol is not a opiet replacement drug it is a drug that you take to block any opiets from being able to fill the brain receptors bacicly it prevents you from getting high....it also is not a substution for aftercare....the only thing I found that helps with the obbession that drive's you to use is the N/A progam.....long after the pills stop your still left with the addict in your head N/A treats the addict with time and working the progam you will loose the desire to get high something I thought was impossible....google a N/A meeting near you you also my want to check out vivitrol's website keep posting for support.................................Gnarly..........................................