Oxymorphone

Oxymorphone (Opana, Numorphan) or 14-Hydroxydihydromorphinone is a powerful semi-synthetic opioid analgesic that is derived from thebaine, and is approximately 6–8 times more potent than morphine. Clinically, it is administered as its hydrochloride salt via injection, or suppository; typically in dosages of 1 mg (injected) to 5 mg (suppository). Endo Pharmaceuticals markets oxymorphone in the United States as Opana and Opana ER. Opana is available as 5 mg and 10 mg tablets; Opana ER, an extended-release form of oxymorphone, is available as tablets in strengths of 5 mg, 10 mg, 20 mg, and 40 mg. As with other opioids, oxymorphone can cause physical dependency, and has the potential for abuse.

Uses
Oxymorphone is indicated for the relief of moderate to severe pain and also as a preoperative medication to alleviate apprehension, maintain anesthesia, and as an obstetric analgesic. Additionally, it can be used for the alleviation of patients with dyspnea associated with acute left ventricular failure and pulmonary edema.

Physical characteristics
Oxymorphone HCl occurs as odorless white crystals or white to off-white powder. It will darken in color with prolonged exposure to light. One gram of oxymorphone is soluble in 4 ml of water and it is slightly soluble in alcohol and ether. The commercially available injection has a pH of 2.7–4.5.

Toxicity
Oxymorphone overdosage is characterized by respiratory depression, extreme somnolence progressing to stupor or coma, skeletal muscle flaccidity, cold and clammy skin, and sometimes bradycardia and hypotension. In a severe case of overdose, apnea, circulatory collapse, cardiac arrest, and death may occur.

Brand Names

 * Numorphan (suppository and injectable solution)
 * Opana (tablet)
 * Opana ER (extended-release tablet)

Illicit Use
Until its removal from the United States market in the early 1970s, oxymorphone in the form of Numorphan 10 mg instant-release tablets was one of the most sought-after and well-regarded opioids of the IV drug using community. Known popularly as "blues" for their light blue color, the tablets contained very few insoluble binders—making them easy to inject—and were extremely potent when used intravenously. "Blues" were also considered to be especially euphoric; comparable to or better than heroin. Numorphan tablets, and the oxymorphone they contained, are the "blues" referred to in the film Drugstore Cowboy.

Oxymorphone is not a component of "T's and blues", 1980s slang for a combination of pentazocine ("T's") and pyribenzamine ("blues").

Chemistry
Oxymorphone is commercially produced from thebaine, a minor constituent of the opium poppy (Papaver somniferum) but found in greater abundance (3%) in the roots of the oriental poppy (Papaver orientale). Oxymorphone can also be synthesized from morphine or oxycodone, and is an active metabolite of the latter drug. The structure-activity relationship of oxymorphone and its derivatives has been well-examined. Esterification of the hydroxyl groups yields stronger compounds. The acetyl ester is 2.5 times more potent and the propenyl ester six times more potent than the parent compound. If the 14-hydroxyl group is formed into the cinnamyl ester, the product is 114 times more potent. The most powerful oxymorphone derviative known is the 14-cinnamyl 3-acetyl ester, which is over 200 times more potent than morphine.