Glutathione (GSH in its reduced state) is a tri-peptide formed from the amino acids L-Cysteine, L-Glutamic acid and Glycine. It's the major endogenous antioxidant, produced in the liver; its remarkable ubiquity means it can block free radical damage in all tissue types. When Professor Luc Montagnier advised the Pope to take a Fermented Papaya Preparation supplement (FPP), he advised him to combine it with reduced Glutathione!
GSH has a number of functions in disease-prevention and in detoxifying the body; GSH deficiency is associated with significantly increased risk of toxicity and disease.
It's even believed, based on several animal and human studies, that GSH deficiency affects the ageing process and reduces life expectancy. A study conducted on centenarians showing that they enjoyed high levels of GSH would seem to support this.
Many studies show that supplementation with selenium, alpha-lipoic acid or N-Acetyl Cysteine can produce a significant increase in intracellular levels of GSH. However, for people with metabolism disorders, or those suffering from cataracts, liver problems or cancer, it may be better to take this nutrient in its preformed form. Contrary to received wisdom, GSH is absorbed intact by the small intestine.
To prolong the activity of this relatively expensive product, and maintain it for longer in its reduced form, it is advisable to take it at the same time as other antioxidants.

Take one or two tablet a day with food, or as advised by your therapist.