Methadone, sold under the brand name Dolophine among others, is an opioid used to treat pain and as maintenance therapy or to help with tapering in people with opioid dependence.
Formula: C21H27NO
Excretion: Urine, faeces
Bioavailability: 41–99% (by mouth)
Onset of action: Rapid
Trade name: Dolophine, Methadose, others
Metabolism: Liver (CYP3A4, CYP2B6 and CYP2D6-mediated)
Biological half-life: 15 to 55 hours