ummmm...the first thing that came to mind was opium.....lol however its highly addictive so I would probably pass on that! lol
other than that I know of no other opiate based meds....sorry

there is some info on novo-cycloprine.....i also knew nothing about that either....lol
http://chealth.canoe.ca/drug_info_de...e_id=816&rot=4