IVIG Dose Calculator

IVIG (intravenous immunoglobulin) is a pooled human plasma product containing concentrated antibodies (IgG). It is used both as replacement therapy for immune deficiencies and, at higher doses, as an immunomodulatory treatment for autoimmune and neurological conditions such as Guillain-Barré syndrome, CIDP, ITP, and Kawasaki disease. Dosing is weight-based and must be prescribed by a physician.

The total dose is body weight multiplied by the prescribed dose per kilogram — for example, 70 kg × 2 g/kg = 140 g total. Guidelines dose IVIG on actual body weight. Some centres adjust the dosing weight for patients with very high BMI; whether any adjustment applies is a decision for the prescribing physician, so discuss it with your doctor.

A total of 2 g/kg is the standard immunomodulatory course described in the EMA core SmPC for human normal immunoglobulin: for example, a starting dose of 2 g/kg in divided doses over 2–5 days for CIDP and multifocal motor neuropathy, 0.4 g/kg/day for 5 days for Guillain-Barré syndrome, and 2 g/kg as a single dose for Kawasaki disease. Individual prescriptions may differ.

Both deliver the same 2 g/kg total: 0.4 g/kg/day over 5 days, or 1 g/kg/day over 2 days. The 5-day regimen gives a smaller daily volume, which some patients tolerate better, while the 2-day regimen shortens the treatment course. Which regimen is appropriate depends on the indication, the product, and patient tolerance — discuss the options with your physician.

Concentration is the amount of immunoglobulin per millilitre: 5% = 50 mg/mL (0.05 g/mL) and 10% = 100 mg/mL (0.1 g/mL). Infusion volume = total grams ÷ grams per mL. So 140 g needs 2,800 mL of a 5% product but only 1,400 mL of a 10% product — the 10% product halves the fluid volume, which can matter for patients with cardiac or renal considerations.

Titration means starting the infusion slowly and increasing the rate stepwise if no reaction occurs. A common pattern is to start at 0.5 mL/kg/hr for 30 minutes, then increase every 30 minutes toward the product's maximum rate. Starting slowly helps detect infusion reactions early. Exact titration steps and maximum rates are product-specific — always follow the product label and the prescriber's orders.

Maximum rates are product-specific, and published data describe a range of about 2–8 mg/kg/min (roughly up to 4.8 mL/kg/hr for a 10% product) as tolerated. The calculator defaults to 4 mL/kg/hr as an illustrative ceiling and lets you change it. The safe maximum for a given patient and product is set by the product label and the prescribing physician — never exceed it.

IVIG is supplied in fixed vial or bottle sizes (for example 5 g, 10 g, 20 g, 30 g), so the calculated dose is rounded to whole vials to avoid waste and partial-vial handling issues. Some hospital protocols round the total dose down to the nearest available vial size. The calculator estimates the number of vials by rounding up; the final rounding decision belongs to the pharmacy and prescriber.

Per the EMA core SmPC, paediatric dosing is also weight-based and not different from adults for each indication, but children must be dosed and monitored by their physician. For adults with obesity, some centres use an adjusted or capped dosing weight because immunoglobulin distributes mainly in plasma and lean tissue — this is a clinical judgment call. Discuss the appropriate dosing weight with your doctor.

No. This calculator produces educational estimates only and is not medical advice. IVIG dosing must be prescribed and supervised by a physician, infusion rates must follow the product label, and infusions must be monitored for reactions by trained staff. If you are a patient, discuss any dosing questions with your doctor; if you are a clinician, verify every figure against the prescription and product monograph before use.