What is the recommended dose of dexamethasone (Acute Respiratory Distress Syndrome - ARDS) treatment?

Dexamethasone Dosing for ARDS

For moderate to severe ARDS, administer dexamethasone 20 mg intravenously once daily for 5 days, followed by 10 mg once daily for 5 days (total 10-day course), initiated within 24 hours of ARDS diagnosis. 1, 2, 3

Evidence-Based Dosing Regimen

The most recent high-quality evidence supports a higher-dose dexamethasone protocol rather than the lower 6 mg dose:

• Days 1-5: Dexamethasone 20 mg IV once daily 1, 2, 3
• Days 6-10: Dexamethasone 10 mg IV once daily 1, 2, 3
• Timing: Initiate within 24 hours of ARDS diagnosis for optimal benefit 1

This regimen demonstrated superior outcomes in the landmark CoDEX trial, which showed a mean increase of 2.26 ventilator-free days compared to standard care (6.6 vs 4.0 days, P=0.04) and reduced 28-day mortality (56.3% vs 61.5%) in COVID-19-associated moderate-to-severe ARDS 3.

Patient Selection Criteria

Eligible patients must meet ALL of the following:

• PaO₂/FiO₂ ratio ≤200 mmHg (moderate ARDS: 100-200; severe ARDS: <100) 4, 2
• Bilateral infiltrates on chest imaging 1
• Mechanical ventilation or high-flow nasal cannula oxygen therapy 4
• ARDS duration <14 days at enrollment 4

Absolute contraindications:

• Active uncontrolled infection without adequate antimicrobial coverage 4
• Intractable hyperglycemia 4
• Active gastrointestinal bleeding 4
• Known hypersensitivity to dexamethasone 4

Alternative Dosing for Late ARDS

For persistent ARDS after day 6 of onset, methylprednisolone may be preferred over dexamethasone due to greater lung tissue penetration 1, 5:

• Methylprednisolone 2 mg/kg/day in divided doses, followed by slow tapering over 13 days 1, 5
• This approach is specifically for late/unresolving ARDS rather than early intervention 1

Critical Monitoring Requirements

Hyperglycemia surveillance is mandatory:

• Monitor glucose levels closely, especially within the first 36 hours after initiating therapy 1, 5
• Insulin therapy may be required in 28-31% of patients 3
• Consider antifungal prophylaxis for patients receiving steroids beyond 48-72 hours 1, 6

Infection surveillance:

• Glucocorticoids blunt the febrile response, requiring heightened vigilance for hospital-acquired infections 1
• Secondary infections occurred in 21.9% of dexamethasone-treated patients in the CoDEX trial 3
• Perform regular sepsis screening with empirical broad-spectrum antibiotics if indicated 1

Tapering and Discontinuation

Never abruptly discontinue corticosteroids after more than a few days of treatment:

• The 10-day dexamethasone protocol includes built-in dose reduction (20 mg → 10 mg) 2, 3
• Abrupt cessation may trigger reconstituted inflammatory response and clinical deterioration 1, 5
• If extending therapy beyond 10 days, taper slowly over 6-14 days rather than 2-4 days 1

Comparison with Lower-Dose Regimens

The evidence strongly favors the 20 mg/10 mg protocol over the 6 mg daily dose:

• The REMED trial was specifically designed to test whether 20 mg is superior to 6 mg in COVID-19 ARDS 4, 7
• Historical data from COVID-19 guidelines suggested 20 mg for critical ARDS with BCRSS score ≥2 1
• The 6 mg dose was primarily studied in broader COVID-19 populations, not specifically moderate-to-severe ARDS 4

Adjunctive Considerations

Maintain lung-protective ventilation throughout steroid therapy:

• Target tidal volume 6 mL/kg predicted body weight per ARDS Network protocol 1, 5
• Corticosteroids address inflammation but do not replace fundamental ventilator management 1

Consider tocilizumab or other immunomodulators only if:

• Concurrent cytokine release syndrome is present 1
• Dexamethasone alone provides inadequate response 1