Nalbuphine is an opioid analgesic used to treat moderate to severe pain. However, the drug may contain impurities that can affect its efficacy and safety. Nalbuphine impurities can be chemical or physical contaminants that result from the manufacturing process. They can include residual solvents, degradation products, and metal impurities. It is important to control and minimize these impurities to ensure the quality and safety of nalbuphine.