IVIg Dosing Guide | IVIGdosing.com

Step 1

Find an indication

Search directly for a condition or browse by department to confirm whether IVIG is recommended, discouraged, or not indicated.

Search First

Two ways to use this guide: type the condition name above, or browse the department and condition fields below.

Common Searches

Tap a common indication to auto-fill the guide

Department

Condition

Select a condition above to see dosage instructions.

Step 2

Calculate the dose

Keep the current formula, but surface the inputs and outputs in a cleaner clinical workflow.

Weight

Actual body weight is always the starting point. Adult obesity adjustments are applied automatically when IBW can be estimated.

Height

Adult height is used to estimate IBW and adjusted body weight. Pediatric and pregnancy modes hide this step.

Gender

Used only for adult IBW estimation in the current calculator.

Prescribed Dosage

g/kg

Dose can be entered manually or auto-populated from a selected indication when IVIG is recommended.

Calculation Results

Ideal Body Weight (IBW) -- kg

Adjusted Body Weight -- kg

Total IVIg Dose

0 g

Daily Plan

Split the total dose across the planned infusion schedule.

Split over

Enter dosage above to see breakdown

Calculations automatically use Adjusted Body Weight for obese patients (BMI > 30) per clinical guidelines.

Stewardship

Evidence-based use and supply reality

IVIG is derived from the pooled plasma of thousands of donors — it is not a synthesized drug. The US supplies approximately 70% of the world's plasma; collection fell 18% during 2020, precipitating global shortages. Prescribing carries both a clinical and a supply responsibility.

Evidence grades by indication

Grade AKawasaki disease — IVIG 2 g/kg reduces coronary artery aneurysm from ~25% to ~4% (Newburger et al., NEJM 1986; AHA Guidelines 2017)
Grade ACIDP — ICE trial: NNT ≈ 4 for sustained response (Hughes et al., Lancet Neurology 2008; Cochrane 2024)
Grade AGBS — Equivalent efficacy to plasmapheresis (van der Meché & Schmitz, NEJM 1992; Cochrane 2014)
Grade AITP (acute) — Rapid platelet augmentation before procedures; not appropriate for long-term maintenance (AAN / ASH Guidelines)
Grade BMyasthenia gravis — AAN Level B evidence for acute exacerbation; equivalent to plasmapheresis short-term
Grade BPrimary immunodeficiency — Established standard of care; reduces serious infections (ESID Guidelines 2020)

Dosing in obesity

Using actual body weight (ABW) in obese patients risks serious overdose. Evidence supports adjusted body weight (AdjBW):

AdjBW = IBW + 0.4 × (ABW − IBW)

Apply when BMI > 30. IBW: males 50 kg + 2.3 kg/inch over 5 ft; females 45.5 kg + 2.3 kg/inch over 5 ft. This calculator uses AdjBW automatically.

Stewardship principles

Confirm indication has evidence-based support before ordering
Use lowest effective dose; taper maintenance where possible
Reassess every 3–6 months — continued need must be documented
Canada is not plasma self-sufficient; each prescription has a supply impact

Adverse Effects

Reactions and serious complications

Overall adverse reaction rate is 25–34% per patient across published pharmacovigilance data (FAERS analysis, 76,138 reports, 2004–2024). Most reactions are mild-to-moderate and infusion-rate dependent. Slowing the infusion rate resolves the majority.

Common — rate dependent, usually resolve with infusion slowing

Headache

Most frequent ADR. Mechanism: vasospasm or sterile meningeal irritation from cytokine release or stabilizing agents. Migraine history is a strong risk factor for post-infusion aseptic meningitis.

Fever / Chills / Myalgia

Incidence ~13–18%. Mechanism: IL-6 and TNF-α release triggered by IgG aggregates or immune complex formation. Premedication with acetaminophen ± diphenhydramine may reduce severity.

Fatigue / Nausea / Flushing

Systemic inflammatory response; transient osmotic fluid shifts. Pediatric data (Côté et al., Transfusion 2025): fever 13.6%, headache 6.7% in children <18 years.

Serious — require monitoring, may necessitate stopping infusion

Anaphylaxis — IgA deficiency

Incidence: 5.7 per 10,000 administrations. Mechanism: trace IgA in IVIG product triggers massive mast cell degranulation in IgA-deficient patients with anti-IgA antibodies. Routine serum IgA screening is not required before first-dose IVIG. Consider IgA level and anti-IgA testing only in patients with a history of prior anaphylactic or recurrent severe allergic reactions to blood products/IVIG; if clinically necessary, product selection may be modified in that setting. Carry epinephrine; monitor during infusion.

→ Screen IgA only if prior anaphylaxis or severe allergy to blood products/IVIG

Aseptic Meningitis Syndrome (AMS)

Incidence: 0.42–0.60%. Onset 24–48 hours post-infusion. Mechanism: direct meningeal irritation by high-dose IgG or stabilizers. Risk factors: high dose (>1 g/kg), rapid infusion rate, personal or family history of migraine. CSF: pleocytosis, elevated protein, sterile cultures. Resolves without treatment in 2–5 days. Recurrence risk with next infusion.

→ Slower rate, NSAIDs, consider lower dose

Hemolysis

Incidence: 0–19% (product and population dependent). Mechanism: passive transfer of donor anti-A/B isoagglutinins coat recipient RBCs → positive DAT, extravascular hemolysis. Non-O blood groups (A, B, AB) at highest risk. Isoagglutinin content is the critical product variable. Definitive systematic review: Cuesta et al., Transfusion 2022. Monitor CBC, LDH, and bilirubin in high-risk patients (blood group A or B, high cumulative dose).

→ Monitor CBC + LDH in non-O blood groups

Thromboembolism

Incidence: ~2.2% per patient. FDA mandated black-box warning in 2013. Mechanism: hyperviscosity from high protein load; possible activation of procoagulant pathways. Risk factors: pre-existing cardiovascular disease, advanced age, obesity, hypercoagulable state, high dose, rapid infusion. Risk mitigation: slow infusion rate, adequate pre-hydration, avoid in acute coronary syndrome. Use AdjBW to avoid overexposure.

→ FDA black-box warning; use AdjBW; slow infusion

Acute Renal Failure

Primarily associated with sucrose-stabilized formulations (e.g., Sandoglobulin, older Gammagard). Mechanism: osmotic nephrosis — sucrose enters proximal tubular cells and impairs renal function. FDA warning issued 1999. Modern non-sucrose formulations (glycine, proline, glucose-stabilized) carry substantially lower renal risk. Risk factors: pre-existing CKD, diabetes, age >65, dehydration, concurrent nephrotoxins.

→ Use non-sucrose products; ensure hydration; monitor Cr

TRALI

Extremely rare with IVIG — approximately 17 total cases reported in the literature. Mechanism: two-hit model — donor HLA or HNA antibodies prime and activate recipient neutrophils in pulmonary microvasculature → non-cardiogenic pulmonary edema. Case fatality rate ~24% in reported case series. Onset within 6 hours of infusion. Treatment: supportive (oxygen, ventilation); no diuretics.

→ Non-cardiogenic pulmonary edema within 6h → TRALI protocol

Pre-infusion Checklist

Patient counseling and pre-treatment screening

The following steps should be completed before the first infusion and reviewed at each subsequent cycle.

Serum IgA screening

Routine serum IgA screening is not required before first-dose IVIG. Consider IgA level and anti-IgA testing only in patients with a history of prior anaphylactic or recurrent severe allergic reactions to blood products/IVIG; if clinically necessary, product selection may be modified in that setting.

Hydration

FDA-mandated counseling point. Ensure adequate oral or IV hydration before and during infusion to reduce risk of renal impairment, thrombosis, and headache. Patients should drink 2L of water in the 24h prior to infusion unless contraindicated.

Blood product consent

IVIG is a pooled human blood product. Discuss the extremely low (but non-zero) risk of transfusion-transmitted infections. Document informed consent per institutional policy.

Vaccination deferral — live attenuated vaccines

IVIG passively transfers antibodies that interfere with immune response to live vaccines. Defer MMR and varicella by 8 months after standard dosing (0.4–0.6 g/kg); defer 11 months after high-dose therapy (≥2 g/kg). Per CDC ACIP and Canadian Immunization Guide. Inactivated vaccines (influenza, COVID-19) can be given at any time.

Symptoms to report immediately

Advise patients to report: shortness of breath or chest tightness (→ TRALI / anaphylaxis), severe headache with stiff neck (→ AMS), dark urine or jaundice (→ hemolysis), leg swelling or acute chest pain (→ VTE), decreased urine output (→ renal). Stop infusion and call provider immediately.

Infusion rate protocol

Start at 0.5–1.0 mg/kg/min; advance in increments every 15–30 minutes if tolerated. Most adverse reactions are infusion-rate dependent — slow the rate before stopping. First-time infusions should always start low and slow, regardless of formulation.