Chemistry/Pharmacology:
Nalbuphine hydrochloride (Nubain®) is classified as a synthetic opioid agonist-antagonist. Chemically, it is related to the opioid antagonist, naloxone and the potent opioid agonist oxymorphone. The chemical name for nalbuphine is 17-(cyclobutylmethyl)-4,5α -epoxymorphinan-3,6 α , 14-triol hydrochloride. It is soluble in water and ethanol and available only as an injectable solution.
Nalbuphine is a potent analgesic. Its analgesic potency is essentially equivalent to morphine. It binds to mu, kappa, and delta opioid receptors. Nalbuphine is metabolized by the liver and excreted by the kidneys.
Illicit Uses:
As an injectable formulation, nalbuphine is primarily used in hospitals and rarely prescribed by physicians compared to other opioid analgesics. In addition, as a drug of abuse it is less attractive as a substitute by heroin addicts or highly tolerant opioid abusers due to its potent antagonist effects. Nalbuphine is ten times more potent than pentazocine as an antagonist and will precipitate withdrawal in an opiate–tolerant individual. A limited number of anecdotal reports suggest that nalbuphine is abused by health care professionals and by body builders (anabolic steroid users).
-from DEA