Phenampromide[1] is an opioid analgesic from the ampromide family of drugs, related to other drugs such as propiram and diampromide. It was invented in the 1960s[2] by American Cyanamid Co.Although never given a general release, it was trialled and 50 mg codeine ≈ 60 mg phenampromide. Tests on the 2 isomers showed that all of the analgesic effects were caused by the (S) isomer. Introduction of a phenyl group to the 4-position of the piperidine-ring produces a drug 60-fold more potent than morphine.[3] The most potent reported derivative is 4-hydroxy-4-phenyl phenapromide which displays analgesic activity some x150 greater than morphine.[4]
Phenampromide produces similar effects to fentanyl, including analgesia, sedation, dizziness and nausea.
Phenampromide is in Schedule I of the Controlled Substances Act 1970 of the United States as a Narcotic with ACSCN 9638 with a zero aggregate manufacturing quota as of 2014. The free base conversion ratio for salts includes 0.88 for the hydrochloride.[5] It is listed under the Single Convention for the Control of Narcotic Substances 1961 and is controlled in most countries in the same fashion as fentanyl.