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"Synthetic narcotic pain reliever commonly used in labor and delivery."
"Nubain is a potent analgesic. Its analgesic potency is essentially equivalent to that of morphine on a milligram basis. Its onset of action occurs within 2 to 3 minutes Its onset of action occurs within 2 to 3 minutes after intravenous administration, and in less than 15 minutes following subcutaneous or intramuscular injection. The plasma half-life of nalbuphine is 5 hours and in clinical studies the duration of analgesic activity has been reported to range from 3 to 6 hours."
