Nalbuphine hydrochloride is a synthetic opioid agonist-antagonist analgesic of the phenanthrene series. It is chemically related to both the widely used opioid antagonist, naloxone, and the potent opioid analgesic, oxymorphone. Chemically nalbuphine hydrochloride is 17-(cyclobutylmethyl)-4,5α-epoxymorphinan-3,6α,14-triol hydrochloride. Nalbuphine hydrochloride molecular weight is 393.91 and is soluble in H2O (35.5 mg/mL at 25ºC) and ethanol (0.8%); insoluble in CHCl3 and ether. Nalbuphine hydrochloride has pKa values of 8.71 and 9.96. The molecular formula is C21H27NO4 ∙ HCl. The structural formula is:
Nalbuphine Hydrochloride Injection is a sterile, nonpyrogenic solution of nalbuphine hydrochloride in water for injection. This product may be administered by subcutaneous, intramuscular or intravenous injection.
Each milliliter (mL) contains nalbuphine hydrochloride 10 mg or 20 mg; sodium citrate, dihydrate 0.47 mg and citric acid, anhydrous 0.63 mg added as buffers and may contain sodium hydroxide and/or hydrochloric acid for pH adjustment; pH 3.7 (3.0 to 4.5). Contains sodium chloride for tonicity adjustment.
Multiple-dose vials contain 1.8 mg/mL methylparaben and 0.2 mg/mL propylparaben added as preservatives. Single-dose products contain no bacteriostat or antimicrobial agent and unused portions must be discarded.