Dioxaphetyl butyrate (INN; trade names Amidalgon, Spasmoxal) is an opioid analgesic which is a diphenylacetic acid derivative, related to other open-chain opioid drugs such as dextropropoxyphene, levacetylmethadol (LAAM), lefetamine and dimenoxadol.[1] [2]
It produces similar effects to other opioids, including dependence, euphoria, analgesia, sedation, constipation, dizziness and nausea.[3]
In the United States it is a Schedule I Narcotic controlled substance with an ACSCN of 9621 and a 2013 annual aggregate manufacturing quota of zero.[4]