Chlorpromazine D6 hydrochloride is primarily used in research and analytical settings as a deuterated internal standard. It is employed in mass spectrometry and chromatography to ensure accurate quantification and identification of chlorpromazine and its metabolites in biological samples. This compound helps in studying the pharmacokinetics, metabolism, and distribution of chlorpromazine in various tissues and fluids. Its deuterated form minimizes interference during analysis, providing reliable data for drug monitoring and toxicological studies. Additionally, it aids in the development and validation of analytical methods for antipsychotic drugs in clinical and forensic laboratories.