There are three primary medications used in MAT for OUD: - Methadone: A long-acting opioid agonist that reduces withdrawal symptoms and cravings. - Buprenorphine: A partial opioid agonist that helps to alleviate withdrawal symptoms and cravings with a lower risk of misuse. - Naltrexone: An opioid antagonist that blocks the effects of opioids, preventing the euphoric and sedative effects.