What is the recommended dose of Intravenous Immunoglobulin (IVIG) for the treatment of Guillain-Barré Syndrome (GBS)?

IVIG Dose in Guillain-Barré Syndrome

The recommended dose of intravenous immunoglobulin (IVIG) for Guillain-Barré Syndrome is 0.4 g/kg body weight daily for 5 consecutive days, totaling 2 g/kg over the treatment course. 1

Standard Dosing Regimen

• Administer IVIG at 0.4 g/kg/day for 5 days (total cumulative dose: 2 g/kg) as first-line treatment for GBS. 1
• This regimen is equally effective as plasma exchange but is preferred due to easier administration, wider availability, and higher treatment completion rates. 1
• Treatment should be initiated as early as possible in the disease course to maximize effectiveness. 1

Pediatric Dosing Considerations

• Use the same 5-day regimen (0.4 g/kg/day for 5 days) in children rather than accelerated 2-day protocols. 2
• A study demonstrated that treatment-related fluctuations (TRFs) occurred more frequently with a 2-day regimen (5 of 23 children) compared to zero TRFs with the standard 5-day regimen (0 of 23 children). 2
• IVIG is preferred over plasma exchange in pediatric patients due to better tolerability and fewer complications. 1

Special Populations

• In pregnant women, IVIG is preferred over plasma exchange because it requires fewer monitoring considerations and additional precautions, though neither treatment is contraindicated during pregnancy. 2, 1
• For patients with Miller-Fisher Syndrome (MFS), treatment is generally not recommended as most recover completely within 6 months without intervention, though close monitoring is essential. 2

Critical Pitfall: Second Dose is NOT Recommended

Do not routinely administer a second course of IVIG (additional 2 g/kg) in patients with poor prognosis, as this increases serious adverse events without improving outcomes. 3

• A high-quality randomized controlled trial (SID-GBS, 2021) demonstrated that a second IVIG course in patients with poor prognosis showed no benefit (adjusted OR 1.4,95% CI 0.6-3.3, p=0.45). 3
• Patients receiving a second dose experienced significantly more serious adverse events (35% vs 16%), including thromboembolic events. 3
• Four deaths occurred in the second-dose group between 13-24 weeks after randomization. 3

Management of Treatment-Related Fluctuations

• For treatment-related fluctuations (TRFs)—defined as disease progression within 2 months after initial treatment-induced improvement—repeat the full 5-day IVIG course (2 g/kg total). 4
• TRFs occur in 6-10% of patients and represent a distinct clinical scenario from poor initial prognosis. 4, 1
• If a patient experiences three or more TRFs and/or clinical deterioration ≥8 weeks after onset, suspect chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) rather than GBS. 4

Pharmacokinetic Variability

• Serum IgG increase (ΔIgG) after standard IVIG dosing varies considerably between patients (mean 7.8 g/L, SD 5.6 g/L), and lower increases correlate with slower recovery. 5
• Despite this pharmacokinetic variability, the evidence does not support routine dose escalation, as the SID-GBS trial demonstrated harm with additional dosing. 3
• Approximately 40% of patients do not show improvement within the first 4 weeks following standard IVIG treatment, which does not necessarily indicate treatment failure. 4, 1

Monitoring After Standard Dosing

• Continue frequent neurological assessments tracking motor function, bulbar symptoms, and respiratory status after completing the 5-day IVIG course. 4
• Monitor pulmonary function including negative inspiratory force and vital capacity, as respiratory compromise can occur even after treatment. 4
• Use the "20/30/40 rule" to assess respiratory failure risk: vital capacity <20 ml/kg, maximum inspiratory pressure <30 cmH₂O, or maximum expiratory pressure <40 cmH₂O. 1
• Most recovery occurs within the first year, with 80% of patients regaining independent walking ability by 6 months. 4, 1