PMID-sentid Pub_year Sent_text comp_official_name comp_offsetprotein_name organism prot_offset 17112806-1 2006 OBJECTIVE: Alfentanil is a short-acting synthetic opioid analgesic, which is extensively metabolized, mainly by hepatic cytochrome P450 (CYP) 3A enzymes. Alfentanil 11-21 cytochrome P450 family 3 subfamily A member 4 Homo sapiens 120-144