N-nitrosamine analysis has raised significant concerns in the pharmaceutical industry since 2018, when these potential carcinogens were found in several angiotensin II receptor blockers (sartans). Subsequent discoveries in ranitidine and some slow-release metformin medications prompted widespread product recalls. The industry has implemented stricter manufacturing requirements and intensified efforts to evaluate and control N-nitrosamine contamination. To meet stringent regulatory requirements, it is essential to develop effective chromatography and mass spectrometry (MS) methods for N-nitrosamine analysis. This blog addresses the challenges associated with detecting N-nitrosodimethylamine (NDMA) in metformin drug products.