Objective: To report the cortisol levels in 6 patients during and after severe inflammation. Design: Patients with severe inflammatory disease had basal and stimulated (cosyntropin) serum cortisol levels determined at the time of severe and less severe inflammation. Setting: Intensive care unit and wards of a tertiary care center. Patients: Six patients with continued evidence of severe inflammation, despite aggressive management of the underlying inflammatory disease. Interventions: Five of 6 patients received hydrocortisone at "physiologic" doses. Main Outcome Measures: Basal and stimulated serum cortisol levels. Results: The mean±SD cortisol data for these patients were as follows: baseline cortisol level during inflammation, 350±121 nmol/L (n=6); stimulated cortisol level during inflammation, 571±326 nmol/L (n=6); baseline cortisol level with less inflammation, 833±339 nmol/L (P=.03 vs baseline level during inflammation) (n=5); and stimulated cortisol level with less inflammation, 1090±295 nmol/L (P=.03 vs stimulated level during inflammation) (n=4). Manifestations of inflammation decreased with hydrocortisone administration. Conclusions: Severe inflammation may result in lowerthan-expected serum cortisol levels, which then increase significantly as the inflammation decreases. Transient hypoadrenalism may aggravate the adverse effects of severe inflammation. These effects may be ameliorated by administering physiologic rather than pharmacologic doses of hydrocortisone.