Nalbuphine

Nalbuphine (nalbuphine hydrochloride) is a synthetic opioid used commercially as an analgesic under a variety of trade names, including Nubain. It is noteworthy in part for the fact that at low dosages, it is found much more effective by women than by men, and may even increase pain in men, leading to its discontinuation in the UK in 2003.
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Nalbuphine /nal·bu·phine/ an opioid analgesic, used as the hydrochloride salt in the treatment of moderate to severe pain and as an anesthesia [more]Nalbuphine - Community and Resources