[4][6] Side effects of nalbuphine include sedation, sweatiness, clamminess, nausea, vomiting, dizziness, vertigo, dry mouth, and headache.
However, a 2014 Cochrane Systematic Review concluded that from the included studies, there was limited evidence to demonstrate that "0.1 to 0.3 mg/kg nalbuphine compared to placebo might be an effective postoperative analgesic" for pain treatment in children.
Therefore, patients receiving an opioid analgesic, general anesthetics, phenothiazines, or other tranquilizers, sedatives, hypnotics, or other CNS depressants (including alcohol) concomitantly with Nalbuphine may exhibit an additive effect.
Kjellberg et al. (2001) published a review of clinical trials relating to the prevalence of morphine induced pruritus and its pharmacologic control.
Pan (1998) summarizes the evidence that activation at the pharmacological level of the KOR antagonizes various MOR-mediated actions in the brain.
The author states that the neural mechanism for this potentially very general MOR-antagonizing function by the KOR may have broad applications in the treatment of central nervous system mediated diseases.
Morphine induced pruritus syndrome may also be caused by release of histamine from mast cells in the skin (Gunion et al. (2004).
Levy et al. (1989) reviewed the literature on the relationship of opioid mediated histamine release from cutaneous mast cells to the etiology of hypotension, flushing and pruritus.
As reported in the current Nubain Package Insert (2005), the most frequent side effect in 1066 patients treated with nalbuphine was sedation in 381 (36%).
Other adverse reactions which may occur (reported incidence of 1% or less) are: Other possible, but rare side effects include speech difficulty, urinary urgency, blurred vision, flushing and warmth.
A 2014 Cochrane Systematic Review by Schnabel et al., concluded that due to limited data, analysis of adverse events for children treated with nalbuphine compared to other opioids or placebo for postoperative pain, could not be definitively reported.
[20] Such effects include sedation (21–36%), dizziness or vertigo (5%), lightheadedness (1%), anxiety (<1%), dysphoria (<1%), euphoria (<1%), confusion (<1%), hallucinations (<1%), depersonalization (1%), unusual dreams (<1%), and feelings of "unreality" (<1%).
Clinical trials studied single dose experimental oral immediate release nalbuphine tablets for analgesic efficacy over a four- to six-hour time period following administration.
Schmidt et al. (1985) reviewed the preclinical pharmacology of nalbuphine and reported comparative data relative to other types of opioid compounds.
The authors point out that the nalbuphine moiety is approximately ten times more pharmacologically potent than the mixed opioid agonist/antagonist butorphanol on an "antagonist index" scale which quantitates the drug's ability to act both as an analgesic (via opioid KOR agonism) as well as a MOR antagonist.
While all drugs in this class possess MOR antagonistic activity leading to less abuse potential, nalbuphine is the only approved drug in the mixed agonist–antagonist class listed in terms of its pharmacological actions and selectivities on opioid receptors as a MOR partial agonist or antagonist as well as a KOR agonist (Gustein et al. 2001).
Nubain, the Astra USA brand name for injectable nalbuphine HCL, was discontinued from being marketed in 2008 in the United States for commercial reasons (Federal Register 2008); however, other commercial suppliers now provide generic injection formulation nalbuphine for the market.