PIP: After a brief summary of the pathophysiology of gram-negative septic shock, a laboratory animal experiment testing the therapeutic efficacy of corticosteroids in such shock cases is presented. Healthy adult mongrel dogs were injected intravenously with 2 mg/kg of E. coli endotoxin to produce endotoxin shock. Overall, the survival of untreated animals was 17% and this was not significantly altered by volume replacement with either Ringers or dextran solution. With treatment (dexamethasone phosphate or methylprednisolone succinate) administered intravenously, in addition to volume replacement, survival increased to 70% of endotoxin-shocked dogs. However, hydrocortisone succinate did not improve survival. The precise mechanism by which the efficacious agents worked is unclear, though both clearly did significantly lower total peripheral vascular resistance. The type of fluid replacement used did not affect the enhanced survival found with dexamethasone phosphate or methylprednisolone succinate.