BUFIGEN is also used as an adjunct to standard or local anaesthesia and to provide pre and postoperative analgesia. It can be used during the 0.33 stage of exertion and diagnostic exam techniques that are potentially traumatic and painful. Pharmacokinetics: Nalbuphine is a potent opioid agonist-antagonist chemically related to naloxone and oxymorphone. It has the same analgesic potential as morphine, mg for mg. Analgesia appears to be produced by agonist actions in key antagonistic actions at mu opioid receptors.
Mu receptors are widely distributed throughout the CNS, particularly in the limbic system, thalamus, striatum, hypothalamus, midbrain, and laminae I, II, IV, and V of the dorsal horn of the spinal wire. Because kappa receptors are concentrated in the spinal cord and cerebral cortex, these sites are involved in the areas where nalbuphine acts. Its movement begins about 2 minutes after being administered intravenously. When administered subcutaneously or intramuscularly, the effect starts within 15 minutes.
Analgesic motion lasts between three and six hours. Nalbuphine binds to plasma proteins approximately 30% of the time. It is metabolized in the liver and has a plasma half-life of 5 hours. It is mainly excreted in the faeces with no current process changes and 7% in the urine as unchanged nalbuphine and conjugated metabolites.