However, theres debate about their effectiveness: Oral GSH has limited bioavailability because it gets broken down in the digestive system
Supplementation of culture medium with L-carnitine improves development and [PMID: 22954232] Laboratory literature summary: Supplementation of culture medium with L-carnitine improves development and cryotolerance of bovine embryos produced in vitro
2 mg subcutaneous daily for 26 weeks, n = 273 active arm): Pooled with injection-site reactions broadly defined (erythema, pruritus, pain, urticaria, hemorrhage, irritation), the total injection-site adverse event rate in the active arm was approximately 25%
& Simon, M
But this creates a cycle that is hard to break and easy to spiral into dependency
Because it is already in its active "reduced" form, your body doesn't have to wait for metabolic conversion to take place