Amantadine-D6 is primarily used in research and analytical applications, particularly as an internal standard in mass spectrometry. Its deuterated form allows for precise quantification of amantadine in biological samples, aiding in pharmacokinetic studies and drug metabolism research. Additionally, it serves as a reference compound in the development and validation of analytical methods for detecting and measuring amantadine in various matrices, such as blood, urine, or tissues. This ensures accuracy and reliability in studies related to its antiviral or antiparkinsonian effects.