Benazepril-d5 is primarily used in research and analytical applications as an internal standard in mass spectrometry. It aids in the quantification and identification of benazepril and its metabolites in biological samples, ensuring accuracy and reliability in pharmacokinetic and drug metabolism studies. This deuterated compound is particularly valuable in clinical research for monitoring therapeutic drug levels and assessing patient compliance. Its stable isotopic labeling minimizes interference, making it a critical tool in advancing precision medicine and drug development.