What is the dose of Intravenous Immunoglobulin (IVIG) for Immune Thrombocytopenic Purpura (ITP)?

From the Guidelines

The standard dose of intravenous immunoglobulin (IVIG) for immune thrombocytopenia (ITP) is 1 g/kg as a one-time dose, which may be repeated if necessary. This recommendation is based on the most recent and highest quality study available, which suggests that IVIG can be used as an alternative to prednisone or dexamethasone for the treatment of ITP 1. The dose of 1 g/kg is also supported by other studies, including the American Society of Hematology guideline on ITP 1.

Administration and Side Effects

IVIG should be administered slowly, starting at 0.5-1 mL/kg/hour for the first 30 minutes, then gradually increasing to a maximum rate of 4-8 mL/kg/hour if tolerated, to minimize infusion reactions. Common side effects include headache, fever, chills, myalgia, and nausea. Premedication with acetaminophen and diphenhydramine may help reduce these reactions.

Mechanism of Action and Duration of Effect

IVIG works by blocking Fc receptors on macrophages, preventing platelet destruction, and typically raises platelet counts within 24-48 hours. The effect is temporary, usually lasting 2-4 weeks, making IVIG appropriate for acute management rather than long-term treatment.

Special Considerations

For patients with renal impairment, the dose may need adjustment and slower infusion rates are recommended. It is also important to note that if previous treatment with corticosteroids and/or IVIG has been unsuccessful, subsequent treatment may include rituximab, thrombopoietin receptor agonists, or more potent immunosuppression 1.

Key Points

• The standard dose of IVIG for ITP is 1 g/kg as a one-time dose
• IVIG can be used as an alternative to prednisone or dexamethasone
• Administration should be slow and gradual to minimize infusion reactions
• Common side effects include headache, fever, chills, myalgia, and nausea
• The effect of IVIG is temporary, usually lasting 2-4 weeks.

From the Research

Dose of Intravenous Immunoglobulin (IVIG) for Immune Thrombocytopenic Purpura (ITP)

The dose of IVIG for ITP varies depending on the study and patient population.

• In children, a dose of 1 g/kg IVIG is recommended initially, with a second dose given if there is an inadequate response 2.
• In adults, a dose of 1 g/kg body weight (b.w.) IVIG is more effective than 0.5 g/kg b.w. 3.
• Low-dose IVIG regimens of 250,400, or 500 mg/kg/day for 2 days are also effective in infants and young children with ITP, with fewer adverse events in children younger than 5 years of age 4.
• A prospective, randomized single-center trial found that high-dose IVIG (2 g/kg) is more effective than low-dose IVIG (0.6 g/kg) in increasing platelet counts within 72 hours in children with acute ITP 5.
• The approved dosage for ITP is 0.4 g/kg daily for 2 to 5 consecutive days, with repeat doses used as maintenance therapy 6.

Key Findings

• The optimal dose of IVIG for ITP is still controversial, with different studies recommending different doses.
• High-dose IVIG may be more effective in increasing platelet counts, but low-dose regimens may be safer and better tolerated, especially in young children.
• The dose and administration of IVIG should be individualized based on the patient's response and adverse event profile.

Adverse Events

• Adverse events associated with IVIG administration are generally mild and transient, but may include headache, nausea, vomiting, and fever.
• Serious adverse events, such as anaphylactoid reactions and aseptic meningitis, are rare but may occur 4.
• Patients with selective IgA deficiency and detectable IgA antibodies should not receive IVIG due to the risk of adverse reactions 6.