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Typical opioids used for pain, including morphine, activate mu opioid receptors. Disadvantages of these drugs include their abuse potential, risk of respiratory depression, and the development of tolerance, dependance, and constipation. Nalbuphine is an injectable opioid agonist-antagonist analgesic with low abuse potential and a unique mechanism of action. Not only is its analgesic potency comparable to morphine within the typical dosing range, but it also has a low risk of clinically significant respiratory depression, and is generally considered much safer than morphine-like opioids. Nalbuphine is not commercially available as an oral product and as such, research on the efficacy of this formulation is limited. While oral nalbuphine has not been studied in chronic pain, the intention of this review is to extrapolate trial data to help determine whether nalbuphine would make a good candidate for use in chronic pain. Oral nalbuphine is effective for the treatment of acute pain and prolonged duration of its use in trials for chronic cough and uremic pruritus have established its safety. The most significant limitation to oral nalbuphine treatment appears to be the frequency of sedation and nausea. The safety and efficacy profile of oral nalbuphine make it a promising therapy option for chronic pain as an alternative to morphine-life opioids, but at this point trials are still needed to make a definitive conclusion.