Generic Names: hydromorphone, dihydromorphinone, dimorphone.Trade/proprietary Names: Dilaudid™, Dilocol™, HydroStat™, Liberaxim™, Opidol™, PMS Hydromorphone™, Sophidone™.Drug Class: opioid analgesic (Class II).Manufacturers: Purdue Pharma, One Stamford Forum, Stamford, CT; Roxane Laboratories, 1809 Wilson Rd, Columbus, OH; Baxter Healthcare, One Baxter Parkway, Deerfield, IL; Abbott Laboratories, 100 Abbott Park Rd, Abbott Park, IL; Barr Laboratories, 223 Quaker Road, Pomona, NY; Richwood-Shire Pharmaceuticals, 5 Riverwalk, Citywest Business Campus, Dublin 24, IrelandChemical Structure: see Figure 23.1.Chemical Name: 4,5-α-epoxy-3-hydroxy-17-methyl morphinan-6-one.Chemical Formula: C17H19NO3; molecular wt: 321. Introduction and description: Hydromorphone is a potent semi-synthetic phenanthrene-derived centrally acting opiate agonist. Hydromorphone is very lipid-soluble, which allows for rapid central nervous system penetration. Hydromorphone is second only to morphine in its use as an analgesic in the acute post-operative setting. It was first researched and synthesized in 1924 in Germany, and marketed by Knoll Pharmaceuticals in 1926 under the brand name Dilaudid™. Hydromorphone hydrochloride is a fine, white or essentially white, crystalline powder and is freely soluble in water and sparingly soluble in alcohol.Mode of activity: Hydromorphone is a hydrogenated ketone derivative of morphine which is about seven to eight times as potent as the parent compound morphine. The duration of action is shorter or similar to morphine at about 4-5 hours. When administered orally or intramuscularly, it retains only about one-fifth the potency of an intravenous dose, and the onset of action is slower, but the duration of action is longer.