Deng Y-N, Xia Z, Zhang P, Ejaz S, Liang S
Researchers were looking for free glutathione levels, and because glutathione is so valuable, it is quickly bound to transport proteins to be carried to cells, causing it to not show up as free glutathione in the blood

For sexual exposure to a person with acute hepatitis B, a single dose of Hepatitis B Immune Globulin (Human) is 75% effective if administered within 2 weeks of last sexual exposure.(9) Since infants have close contact with primary care-givers and they have a higher risk of becoming HBV carriers after acute HBV infection, prophylaxis of an infant less than 12 months of age with Hepatitis B Immune Globulin (Human) and hepatitis B vaccine is indicated if the mother or primary care-giver has acute HBV infection.(9) Administration of Hepatitis B Immune Globulin (Human) either preceding or concomitant with the commencement of active immunization with Hepatitis B Vaccine provides for more rapid achievement of protective levels of hepatitis B antibody, than when the vaccine alone is administered.(17) Rapid achievement of protective levels of antibody to hepatitis B virus may be desirable in certain clinical situations, as in cases of accidental inoculations with contaminated medical instruments.(17) Administration of Hepatitis B Immune Globulin (Human) either 1 month preceding or at the time of commencement of a program of active vaccination with Hepatitis B Vaccine has been shown not to interfere with the active immune response to the vaccine.(17) HyperHEP B is made from human plasma

Singh RK, Kumar S, Prasad DN, Bhardwaj TR
Glutathione is studied for its role as the body's master intracellular antioxidant