https://medixway.com/methadone-vs-buprenorphine/ 

Methadone is an opioid analgesic drug and it’s a generic drug. People use this drug for opioid use disorder (OUD) and to manage pain. This FDA-approved medicine is classified as a Schedule II controlled substance under the Controlled Substances Act (CSA).Buprenorphine is a generic drug, and it is available as an active ingredient in other drugs. It is also a prescription medication. This buprenorphine drug is approved by the Food and Drug Administration (FDA) to treat OUD and acute to chronic pain in patients.It helps in reducing the craving and withdrawal symptoms without causing any serious side effects in individuals.