minor constituent of the opium poppy (Papaver somniferum) but thebaine is found in greater abundance (3%) in the roots of the oriental poppy (Papaver orientale). German patents from the mid-1930s indicate that oxymorphone as well as hydromorphone, hydrocodone, oxycodone, and acetylmorphone can be prepared—without the need for hydrogen gas—from solutions of codeine, morphine, and dionine by refluxing an acidic aqueous solution, or the precursor drug dissolved in ethanol, in the presence of certain metals, namely palladium and platinum in fine powder or colloidal form or platinum black. Oxymorphone hydrochloride occurs as odourless white crystals or white to off-white powder. It darkens in colour with prolonged exposure to light. One gram of oxymorphone hydrochloride is soluble in 4 ml of water and it is sparingly soluble in alcohol and ether. It degrades upon contact with light. Oxymorphone can be acetylated like morphine, hydromorphone, and some other opioids. Mono-, di-, tri-, and tetra- esters of oxymorphone were developed in the 1930s but are not used in medicine at this time. Presumably other esters such as nicotinyl, benzoyl, formyl, cinnimoyl &c.can be produced. The 2013 US DEA annual manufacturing quotas were 18 375 kilogrammes for conversion (a number of drugs can be made from oxymorphone, both painkillers and opioid antagonists like naloxone) and 6875 kg for direct manufacture of end-products. Oxymorphone is also a minor metabolite of oxycodone, which is formed by CYP2D6-mediated O-demethylation. History Oxymorphone was first developed in Germany in 1914, and patented in the US by Endo Pharmaceuticals in 1955. It was introduced in the United States in January 1959 and other countries around the same time. Society and culture Brand names Numorphan (suppository and injectable solution) Opana ER (extended-release tablet): June 2017 FDA removal request due to rates of IV abuse. Opana IR (immediate-release tablet) O-Morphon in Bangladesh by Ziska pharmaceutical ltd. The brand name Numorphan is derived by analogy to the Nucodan name for an oxycodone product (or vice versa) as well as Paramorphan/Paramorfan for dihydromorphine and Paracodin (dihydrocodeine). The only commercially available salt of oxymorphone in most of the world at this time is the hydrochloride, which has a free base conversion ratio of 0.891, and oxymorphone hydrochloride monohydrate has a factor of 0.85. Generic pill markings are ATV10/APO; HK10 (10 mgs) oblong white and ATV20/APO; HK20 (20 mgs) oblong white. Abuse In 1924, the United States Congress had banned the sale, importation, or manufacture of heroin,