<unk>  (INN), levomethadyl acetate (USAN), OrLAAM (trade name) or levo-α-acetylmethadol (LAAM) is a synthetic opioid similar in structure to methadone. It has a long duration of action due to its active metabolites. It was approved in 1993 by the U.S. Food and Drug Administration for use in the treatment of opioid dependence. In 2001, Orlaam was removed from the European market due to reports of life-threatening ventricular rhythm disorders. In 2003, Roxane Laboratories, Inc. discontinued Orlaam in the US.
Levacetylmethadol
Acetylmethadol
Nalorphine
Meperidine 
Phenazocine
Propentofylline
Dyclonine hydrochloride
Naloxone