Displaying 2 results of Meperidine Stable Isotopes Meperidine Stable Isotopes are non-radioactive isotopes of meperidine, also known as pethidine, a synthetic opioid pain medication. These isotopes have the same number of protons and electrons as the naturally occurring meperidine, but differ in the number of neutrons in the nucleus. They are used in research and clinical studies to trace and monitor the metabolism and pharmacokinetics of meperidine, as well as for calibration of analytical instruments. Meperidine Stable Isotopes are safe and reliable tools for precise and accurate measurement of meperidine in biological samples.