What are the weight‑based dosing regimens for IV Solu‑Medrol (methylprednisolone sodium succinate) for its various clinical indications?

Weight-Based IV Solu-Medrol (Methylprednisolone) Dosing by Indication

For high-dose pulse therapy in life-threatening conditions, administer 30 mg/kg IV over at least 30 minutes, repeated every 4-6 hours for up to 48 hours, as this is the FDA-approved weight-based regimen for severe acute situations. 1

FDA-Approved Weight-Based Dosing

High-Dose Emergency Therapy

• 30 mg/kg IV over at least 30 minutes is the standard high-dose regimen 1
• May be repeated every 4-6 hours for 48 hours 1
• Continue only until patient stabilizes, typically not beyond 48-72 hours 1
• Critical safety warning: Doses >0.5 grams administered in <10 minutes have caused cardiac arrhythmias and arrest 1

Pediatric Weight-Based Dosing

• Initial dose range: 0.11-1.6 mg/kg/day divided into 3-4 doses 1
• For asthma exacerbations: 1-2 mg/kg/day in single or divided doses 1
• Minimum dose should not be <0.5 mg/kg every 24 hours 1

Disease-Specific Weight-Based Regimens

Multisystem Inflammatory Syndrome in Children (MIS-C)

• First-line: 1-2 mg/kg/day IV methylprednisolone 2
• Intensification for refractory disease: 10-30 mg/kg/day IV 2
• Use ideal body weight for IVIG dosing (2 gm/kg), which is co-administered 2

Autoimmune/Rheumatologic Conditions

• Pulse therapy: 10-20 mg/kg or 250-1000 mg daily for 1-5 consecutive days 3
• Severe organ-threatening disease: 500-1000 mg IV daily for 1-3 days 3
• Macrophage activation syndrome: 15-30 mg/kg/day (maximum 1 g/infusion) 3

Cardiac Transplant Rejection (Pediatric)

• Day 1: 20 mg/kg IV (maximum 1000 mg) 3
• Day 2: 10 mg/kg IV (maximum 500 mg) 3
• Day 3: 5 mg/kg IV (maximum 250 mg) 3

Severe Immune-Related Adverse Events

• Grade 3-4 neurotoxicity: 1000 mg IV daily for 3-5 days 3
• May consider 1000 mg twice daily for grade 4 events 3
• For CAR T-cell therapy complications: 1 mg/kg IV every 12 hours for grade 3, or 1000 mg daily for 3-5 days 3

Spinal Cord Injury (Historical—Not Currently Recommended)

• 30 mg/kg IV bolus over 15 minutes within 8 hours of injury 4
• Followed by 5.4 mg/kg/hour continuous infusion for 23 hours 4
• Important caveat: This is only a treatment option with weak evidence and is no longer standard of care 4

Critical Dosing Considerations

Administration Safety

• Never administer >0.5 grams in <10 minutes due to cardiac arrest risk 1
• High-dose therapy (30 mg/kg) must be infused over ≥30 minutes 1
• Bradycardia may occur unrelated to infusion speed with large doses 1

Weight Calculation

• Use ideal body weight for children <40 kg 5
• For children ≥40 kg, transition to adult dosing protocols 5
• Avoid using actual weight in obese patients to prevent overdosing 5

Monitoring Requirements

• Glucose: Check before each infusion and every 4-6 hours for 24 hours, with peak hyperglycemia at 6-9 hours post-dose 3
• Electrolytes: Monitor potassium and sodium throughout therapy, especially with renal impairment 3
• Blood pressure: Monitor during infusion 3

Post-Pulse Transition

Conversion to Oral Therapy

• Transition to oral prednisone at 0.5-1 mg/kg/day (maximum 60 mg/day) 3
• Use 1:1.25 conversion ratio (1 mg IV methylprednisolone = 1.25 mg oral prednisone) 3
• Taper gradually over 3-6 months based on clinical response 3

Steroid-Sparing Agents

• Azathioprine 1-3 mg/kg/day as first-line maintenance 3
• Mycophenolate mofetil 1 gram twice daily as alternative 3
• Consider antifungal prophylaxis during high-dose therapy 3

Common Pitfalls to Avoid

• Do not use adult fixed doses in children <40 kg—always calculate mg/kg 5
• Do not infuse rapidly—cardiac complications occur with rapid administration of large doses 1
• Do not continue beyond 48-72 hours for high-dose emergency therapy unless specifically indicated 1
• Do not abruptly discontinue after prolonged therapy—taper gradually 1
• Do not forget glucose monitoring—hyperglycemia peaks 6-9 hours post-dose 3