Metopon

Metopon (5-methylhydromorphone hydrochloride) is an opiate analogue that is a methylated derivative of hydromorphone which was invented in 1948 as an analgesic.

Metopon is sometimes used in medicine, but although longer acting than hydromorphone, metopon is less potent and has poor oral bioavailability, so generally has few advantages to distinguish it from other, more commonly used opioid analgesics. It has similar side effects to other opiates, which include itching, nausea and respiratory depression.

CAS number 124-92-5 (Metopon hydrochloride)