Displaying 1 results of Methadone Impurities Methadone is a synthetic opioid medication used to treat pain and opioid addiction. However, during the manufacturing process of the drug, impurities may be introduced that can affect its safety and effectiveness. These impurities may include residual solvents, degradation products, and other contaminants. Proper monitoring and control of impurities are essential for ensuring the quality and safety of methadone products.