Displaying 2 results of Methadone Stable Isotopes Methadone Stable Isotopes are non-radioactive forms of the drug methadone that have identical chemical and physical properties as the naturally occurring form, but with a slightly different atomic mass. They are used in research and medical applications to track the metabolism and distribution of methadone in the body, and to study the drug's effects on various physiological processes. Methadone Stable Isotopes are valuable tools for advancing our understanding of opioid addiction and developing more effective treatments for this complex condition.