S-Acetyl-L-glutathione is a derivative of glutathione .1 It increases intracellular GSH levels in primary fibroblasts derived from patients with glutathione synthetase deficiency when used at a concentration of 50 μM. S-Acetyl-L-glutathione (5 mM) induces apoptosis in Daudi, Raji, and Jurkat lymphoma cells.2 It inhibits the replication of herpes simplex virus 1 (HSV-1) in human foreskin fibroblasts when used at concentrations of 5 and 10 mM.3 S-Acetyl-L-glutathione (6.25 μg/g per day) increases survival in a mouse model of HSV-1 infection.