Opana Er is an Opana Extended-Release tablet. Opana ER is the brand name, its generic drug is Oxymorphone hydrochloride. It is directed to manage extreme pain. Buy Opana ER online for use when an around-the-clock opioid pain reliever is needed. Regular long-term use of this medicine will lead to addiction and it has a high chance of abuse. Oxymorphone was first produced in 1914 by Germans.