PMID-sentid Pub_year Sent_text comp_official_name comp_offsetprotein_name organism prot_offset 34513628-6 2021 Tramadol, as an opioid-like analgesic, is mainly metabolized into O-desmethyl tramadol (M1), by CYP2D6 and undergoes N-demethylation to M2, by CYP2B6 and CYP3A4. Tramadol 0-8 cytochrome P450, family 2, subfamily b, polypeptide 3 Rattus norvegicus 143-149