Displaying 3 results of Diflunisal Stable Isotopes Diflunisal Stable Isotopes are isotopically-labeled forms of the nonsteroidal anti-inflammatory drug, diflunisal. These isotopes are chemically identical to the natural form of diflunisal, but contain a specific number of stable isotopes of carbon, nitrogen, or hydrogen. They are used in pharmacokinetic studies to track the absorption, distribution, metabolism, and excretion of diflunisal in the body.