If the deficiency was purely dietary, oral supplementation may be considered after initial repletion
[1] One trial did find that oral supplementation of glutathione did have an effect on increasing your body's level of glutathione, indicating that at least some of it does still get through your system to take effect
Broad Connectivity Map analysis has revealed that GHK-Cu modulates the expression of over 4,000 human genes, representing approximately 6% of the genome
PLoS ONE 6(4):e18815 Jose N, Joel A, Selvakumar RJ, Ramireddy J, John AO, Georgy JT, Singh A, Ram TS (2022) Diagnosis and management of 5-fluorouracil (5-FU)-induced acute leukoencephalopathy: lessons learnt from a single-Centre case series
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