A clinician's guide to corticosteroid therapy in pneumonia and critical illness: agent selection, dosing, monitoring, and interactions.

Corticosteroids are cornerstone therapies in critically ill patients with severe pneumonia, acute respiratory distress syndrome (ARDS), and septic shock. However, their optimal application requires nuanced, syndrome-specific decision-making rather than a "one-size-fits-all" approach. This review provides a practical, evidence-based framework tailored specifically for adult patients in the ICU, defining a clear target audience of intensivists, pulmonologists, infectious disease specialists, and critical care pharmacists. We focus on six pillars: (1) the pathophysiology of critical illness-related corticosteroid insufficiency (CIRCI); (2) syndrome-specific agent selection supported by landmark trials; (3) precise dosing, administration, and tapering strategies; (4) structured safety monitoring; (5) management of high-risk drug-drug interactions; and (6) a comparative analysis of efficacy across agents. By synthesizing data from the CAPE COD, RECOVERY, DEXA-ARDS, APROCCHSS, and ADRENAL trials alongside the 2024 SCCM/ESICM focused guidelines, this guide offers a bedside roadmap for optimizing corticosteroid therapy in the ICU. Important distinctions are made between viral etiologies (benefit in COVID-19, systematic harm in influenza), and clinical exceptions are clearly defined. A dedicated section addresses the unique challenges of corticosteroid use in immunocompromised hosts, a population systematically excluded from landmark trials but increasingly encountered in ICU practice. Practical algorithms, monitoring tables, and drug interaction checklists are provided to support real-time clinical decision-making.