I'd also strongly recommend against Vivitrol, but what a lot of people don't understand is that a lot of the people who get the shot are essentially being forced into it. Not literally, but take for example my situation (I've been on it since last March, probably going to have to do 2 or 3 more months). Many younger people are in the same boat.
A year and a half ago, conveniently right before I graduated high school, I got arrested for selling adderall and from there my parents figured out I was into opiates, so they sent me to rehab. The treatment center convinced me and my parents into starting Vivitrol, which is covered 100% by insurance for me. The first month or two, I was happy and excited and relieved that the option of using was out of the question, but inevitably, like everyone else I was in rehab with who got the shot, after a while, it became a torture device. After a few months I stopped getting the shot, relapsed, they found out, and I was given an ultimatum to get the shot for 12-18 months or be cut off completely and all that shit. I think they know it's not actually a "magic bullet cure for addiction", but it seems like the purpose of the shot is to give the people close to you peace of mind and security for a while. Kind of sad. Sometimes, at the end of the month when I'm about to get the next shot, I'll IV a couple milligrams of hydromorphone or take a quarter of an 8mg sub strip (bupe actually has a stronger binding affinity to the mu-receptors than naltrexone theoretically, but it's not that great, not even IV'ed which is terrible for your veins and should never be done anyways). Sometimes at the end of the month you can get a slight body euphoria, but everyone is right when they say you're not going to get the feeling you want if you're on the shot. Just a disappointing, nostalgic and bland kind of high that will leave you depressed and wanting the real thing again.
Benefits of Vivitrol: Because you will not be using (or at least not using successfully) anymore, if you stay on it for the recommended 12-18 months, your brain will likely recover from the neurological damage that opiate addiction causes. I do feel a subtle difference after 10 months, it wouldn't be fair to deny that. It does give the people around you a sense of security, but not forever, and only if they're still naive about addiction. If you can manage to be satisfied with the high you can get later in the month, I guess one could see Vivitrol as a way of making you set limits, but that's not the purpose of the shot, you can't do Vivitrol forever, and when that time comes to take off your training wheels, if you're not in recovery and you're still planning on using at all, you'll be back to square one eventually.
Downside of Vivitrol: There are plenty of other types of drugs you can still feel; since starting the shot, I've started and kicked short addictions to meth, alcohol, and benzos. Unless you're 100% serious about sobriety for good and you stay serious, in which case I'd doubt you need the shot in the first place, the frustration and depression you end up having is the shittiest feeling there is besides being dopesick. I've met hundreds of people in recovery and a dozen or two on vivitrol, and this is just my experience, but the ones who really push through and stay sober aren't on it.
I can't really answer OP's question, sorry, but I felt the need to post this because vivitrol isn't much of a widely used or commonly known medication, and like myself, there could be people out there on this shot who are looking for more relevant answers to their questions, not someone saying "i don't know what vivitrol is but go to meetings don't get high". That's what anyone should do, if they've gotten to the point in their lives where vivitrol has been introduced to them, but most people on the shot intend on using again.
By the way, for the sake of HR, I still strongly urge anyone who is getting this shot to give sobriety a chance, and if you're not going to and want to try and get high on the shot, please don't risk your life or your veins by doing high doses of anything as your tolerance is reset, or by IVing pills that everyone on Bluelight says are dangerous to shoot without micron filters. Even if you think an opiate high is worth the risk, the miniscule buzz you'll get isn't.
