IVIG Dosing
The standard IVIG dose is 0.4 g/kg/day for 5 consecutive days (total cumulative dose of 2 g/kg), though specific clinical indications may require different dosing strategies.
Dosing by Clinical Indication
Immune Checkpoint Inhibitor-Related Neurologic Toxicities
For severe myasthenia gravis (Grade 3-4) associated with immune checkpoint inhibitors:
- Total dose: 2 g/kg IV over 5 days (0.4 g/kg/day × 5 days) 1, 2, 1
- Alternative: Single dose of 2 g/kg may be considered 2
- Must be combined with corticosteroids (methylprednisolone 2-4 mg/kg/day)
- Requires ICU-level monitoring with frequent pulmonary function assessments
For Guillain-Barré syndrome (all grades):
- 0.4 g/kg/day for 5 days (total 2 g/kg) 2, 1
- Concurrent corticosteroids recommended (methylprednisolone 2-4 mg/kg/day or pulse dosing 1 g daily × 5 days)
- Critical caveat: Plasmapheresis immediately after IVIG will remove immunoglobulin—do not administer sequentially 2
Primary Immunodeficiency
For replacement therapy:
- 300-600 mg/kg every 3-4 weeks 3
- Initial infusion rate: 0.01 mL/kg/min (0.5 mg/kg/min)
- Maintenance rate (if tolerated): up to 0.10 mL/kg/min (5 mg/kg/min) 3
- Adjust dose to achieve target trough IgG levels (typically >6 g/L for optimal infection prevention) 4
- For measles exposure: 400 mg/kg as soon as possible within 6 days of exposure 3
Immune Thrombocytopenia (ITP)
For first-line treatment:
- 1 g/kg as a single dose, may repeat if necessary 5
- Alternative: 0.4 g/kg/day for 2-5 consecutive days 6
- Use with corticosteroids when rapid platelet increase required 5
Weight-Based Dosing Considerations
Use actual body weight for dosing calculations in most clinical scenarios 7, 4. While ideal body weight dosing has been explored for ITP with potential cost savings, actual body weight dosing remains standard practice 8.
Important exception: In obese patients with primary immunodeficiency, body-weight-adjusted dosing is necessary to achieve adequate IgG trough levels and reduce infection risk 4.
Infusion Rate and Administration
Standard protocol:
- Start at 0.01 mL/kg/min (0.5 mg/kg/min) 3
- If tolerated after 30 minutes, gradually increase to maximum 0.10 mL/kg/min (5 mg/kg/min)
- Monitor vital signs throughout infusion
- Slow or stop if adverse reactions occur
For patients at thrombosis risk (advanced age, immobilization, hypercoagulability, cardiovascular disease):
- Use minimum dose and infusion rate practicable 3
- Ensure adequate hydration before administration
- Monitor for signs of thrombosis and hyperviscosity
Dose Adjustment and Monitoring
Primary Immunodeficiency
- Adjust dose based on clinical response and trough IgG levels 3
- Target trough IgG >6 g/L associated with lower infection rates 4
- Higher doses (>600 mg/kg) may be needed for adequate protection 4
- Frequency varies by patient (every 21-28 days typical) 9
Chronic Inflammatory Demyelinating Polyneuropathy (CIDP)
- Initial dose typically 2 g/kg, then titrate downward 10
- Dose reductions of 42-88% often achievable while maintaining efficacy 10
- Treatment frequency remains fixed per patient (cannot be extended) 10
- Mean maintenance: 866 mg/kg/dose every 28 days 11
Critical Safety Considerations
Contraindications:
High-risk populations requiring dose/rate modification:
- Renal insufficiency (any degree), diabetes, age >65, volume depletion 3
- Thrombosis risk factors 3
- First-time recipients or those not treated in previous 8 weeks 6
Monitor for hyperviscosity in older children/adolescents receiving high-dose therapy (2 g/kg), as serum IgG increases may be greater than in younger children 12. Consider monitoring serum IgG, total protein, and hematocrit when administering repeated high doses.
Product-specific note: Sucrose-containing IVIG products carry higher renal failure risk—avoid in at-risk patients 3.