ascorbic acid with glutathione Life Extension Glutathione, Cysteine & C, 100 Capsules Glutone 1000Mg Effervescent Tablets, 15S

And reviews showed others did, too

Volume check: The total liquid volume in the vial should match the amount of water you added, plus the negligible volume of the dissolved peptide

Animals, including humans, can convert cyanocobalamin to any one of the active vitamin B 12 compounds

doi: 10.3390/ijerph10126442 126 RupaDSReddyPPReddiOS

It is important to note that while injectable glutathione is sometimes used for certain patients undergoing chemotherapy, few studies on glutathione and the skin have been done and there is currently no conclusive evidence regarding glutathione and skin (particularly injectable glutathione for skin whitening)

Denmark Research suggests they may support nerve repair, enhance cognitive function, and protect against neurodegenerative conditions, though more studies are needed to confirm their efficacy and safety for these purposes