intravenous glutathione pharmacokinetics half life human for skin lightening: Inadequate safety data Frontiers | Review of the

The review documented DSIP's widespread distribution throughout the brain and peripheral tissues, its remarkably stable presence in cerebrospinal fluid, and its unusually long-lasting biological effects despite a short plasma half-life of only minutes

10.1038/nature04634 20 JacobsenD

"Two concentrations of topical tretinoin (retinoic acid) cause similar improvement of photoaging but different degrees of irritation: a double-blind, vehicle-controlled comparison of 0.1% and 0.025% tretinoin creams." Archives of dermatology 131.9 (1995): 1037-1044

Studies found wounds treated for 13 days healed much faster than untreated ones