Glutathione is safe for most adults when taken by mouth, by inhalation, or by injection into the muscle or into the veins. It doesn't harm an adult human body. Sometimes, it's needed based on your body requirements. For example, if you have an extreme hangover, Glutathione can help you out from the hangover.
However, during pregnancy and breastfeeding period women can avoid this substance. They can stay on the safe side and avoid the use of Glutathione. But other than every adult human can take Glutathione with the proper dose.
You can take a look at some substances like Glutathione which is needed for the human body for a sickness condition...
Right Dose for Glutathione:
If you are taking it intravenously, take 2gms of Glutathione for safer use.