Background: Glutathione injections for skin whitening have been widely used recently in capricious dosing regimens with no scientific evidence. The overall safety data on injectable glutathione are scarce. Objective: This study aims to investigate the potential toxic doses of injected glutathione, the possibility of inducing different organ dysfunction, and the recovery pattern if it occurs. Methods: Glutathione was injected intramuscularly into rats in two different high doses, 124mg/kg and 248mg/kg (G II& III), twice per week for 13 weeks with the control group (G I) in which rats did not receive the drug. Rats were sacrificed 1 hour, 1 week and 2 weeks after the last administered dose. The liver, kidneys, and heart underwent histopathological and biochemical analysis. Results: The results revealed that at a dose of 124 mg/kg, no toxic effect was shown on the liver, kidney, or heart. However, doubling the dose to 248mg/kg caused a toxic impact on the liver, which recovered 2 weeks after the last dose, and the kidney, with no recovery observed. No affection on the heart. Conclusions: Glutathione injection is proven to have a potentially toxic effect when given at a dose of 248 mg/ kg twice / week for 13 weeks in rats. So, the drug dose must be adjusted for its possible toxicity.