Suboxone is made up of Buprenorphine, a partial opioid agonist with a high affinity for mu-opioid receptor. Basically, that part of Suboxone reduces opioid cravings. Suboxone is also made up of Naloxone. Naloxone helps works as an antagonist and helps block any opioid in the your system.
Vivitrol (Naltrexone) is a once every 28 day shot that is a pure antagonist. It works by blocking the opioid receptors in your brain from receiving any pleasure from taking opioids. Vivitrol is non-addictive and can be used for Alcoholism as well. Visit https://www.vivitrol.com/About/HowVIVWorksOPD