Metopon is a powerful opioid painkiller that has been discontinued for quite some time now. As it is no longer available, it is important to know some synonyms for it in case you come across them in medical prescriptions or literature. Some of the common names used are dibenzoylmorphine, Peronine, Methyldesorphine, and Desomorphine. Another name used is acetylpropionylmorphine, which is a semisynthetic opioid that is used to relieve pain. Though these drugs have similar effects to metopon, they differ in their level of potency and side effects. It is important to seek medical advice before using any pain medication to avoid any complications and addiction.