Creatine-d3 is the deuterium labeled Creatine[1]. Creatine, an endogenous amino acid derivative, plays an important role in cellular energy, especially in muscle and brain[2].
Stable heavy isotopes of drogen, carbon, and other elements have been incorporated into drug molecules, largely as tracers for quantitation during the drug development process. Deuteration has gained attention because of its potential to affect the pharmacokinetic and metabolic profiles of drugs[1].
References:
[1]. Russak EM, et al. Impact of Deuterium Substitution on the Pharmacokinetics of Pharmaceuticals. Ann Pharmacother. 2019 Feb;53(2):211-216.
[2]. Nouioua S, et al. Creatine deficiency syndrome. A treatable myopat due to arginine-glycine amidinotransferase (AGAT) deficiency. Neuromuscul Disord. 2013 Aug;23(8):670-4.