Oxymorphone (sold under the brand names Numorphan and Opana among others) is a highly potent opioid analgesic indicated for treatment of severe pain. Pain relief after injection begins after about 5–10 minutes, after oral administration it begins after about 30 minutes, and lasts about 3–4 hours for immediate-release tablets and 12 hours for extended-release tablets. The elimination half-life of oxymorphone is much faster intravenously, and as such, the drug is most commonly used orally. Like oxycodone, which metabolizes to oxymorphone, oxymorphone has a high potential to be abused. It was developed in Germany in 1914. It was patented in 1955 and approved for medical use in 1959. In June 2017 the FDA asked Endo Pharmaceuticals to remove its product from the US market. This was in part due to the opioid epidemic in the US, and the fact that a 2012 reformulation failed to stop illicit injection of the drug. Endo responded by voluntarily removing Opana ER from the market a month later. Generic versions of extended-release oxymorphone, such as those manufactured by Amneal Pharmaceuticals, are still available in the US. Medical uses Oxymorphone Immediate Release is indicated for the relief of moderate to severe pain, such as treatment of acute post surgical pain. For any chronic treatment of pain, clinicians should only consider long term use if there is significant clinical benefit to the patient's therapy that outweigh any potential risk. The first line treatment choices for chronic pain are non-pharmacological and non-opioid agents. Oxymorphone extended-release tablets are indicated for the management of chronic pain and only for people already on a regular schedule of strong opioids for a prolonged period. Immediate-release oxymorphone tablets are recommended for breakthrough pain for people on the extended-release version. Compared to other opioids, oxymorphone has similar pain relieving efficacy. In the United States it is a Schedule II controlled substance with an ACSCN of 9652. Oxymorphone ER Tablets should be taken on an empty stomach. Availability Brands and forms Oxymorphone is marketed by a single brand name manufacturer, Endo Pharmaceuticals, under the brand name(s) Opana and Opana ER. Opana ER was withdrawn by the manufacturer in 2017, making it unavailable in the US. However, both IR (immediate release) and ER (extended release) formulations are available under the generic name Oxymorphone and Oxymorphone ER, provided by a multitude of different laboratories. Oxymorphone is also available as an injectable for inpatient use, available for IV