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Gammaplex Dosage

Generic name: HUMAN IMMUNOGLOBULIN G 5g in 50mL
Dosage form: injection, solution
Drug class: Immune globulins

Medically reviewed by Last updated on Jun 29, 2023.

For Intravenous Use Only


Table 1: Recommended Dosage and Administration for GAMMAPLEX 10%
Indication Dose Initial infusion rate Maintenance infusion rate (if tolerated)
PI 300-800 mg/kg (3-8 mL/kg) every 3-4 weeks 0.5 mg/kg/min (0.005 mL/kg/min) for 15 minutes Increase gradually every 15 minutes to 8 mg/kg/min (0.08 mL/kg/min)
ITP 1 g/kg (10 mL/kg) for 2 consecutive days 0.5 mg/kg/min (0.005 mL/kg/min) for 15 minutes Increase gradually every 15 minutes to 8 mg/kg/min (0.08 mL/kg/min)

Treatment of Primary Humoral Immunodeficiency

As there are significant differences in the half-life of IgG among patients with PI, the frequency and amount of immunoglobulin therapy may vary from patient to patient. The proper amount can be determined by monitoring clinical response.

The recommended dose of GAMMAPLEX 10% for patients with PI is 300 to 800 mg/kg (3 to 8 mL/kg), administered every 3 to 4 weeks. If a patient has been exposed to measles, it may be prudent to administer an extra dose of Immune Globulin Intravenous as soon as possible and within 6 days of exposure. A dose of 400 mg/kg should provide a serum level > 240 mIU/mL of measles antibodies for at least two weeks. If a patient is at risk of future measles exposure and receives a dose of less than 530 mg/kg every 3-4 weeks, the dose should be increased to at least 530 mg/kg. This should provide a serum level of 240 mIU/mL of measles antibodies for at least 22 days after infusion. Adjust the dosage over time to achieve the desired serum trough levels and clinical response. If a patient misses a dose, administer the missed dose as soon as possible, and then resume scheduled treatments every 3 or 4 weeks, as applicable.

Treatment of Chronic Immune Thrombocytopenic Purpura

The recommended dose of GAMMAPLEX 10% for patients with ITP is 1 g/kg (10 mL/kg) on 2 consecutive days, providing a total dose of 2 g/kg. Carefully consider the relative risks and benefits before prescribing the high dose regimen (i.e. 1 g/kg/day for 2 days) in patients at increased risk of thrombosis, hemolysis, acute kidney injury, or volume overload [see Warnings and Precautions (5)]. Adequate data on the platelet response to the low dose regimen (e.g. 400 mg/kg per day for 5 consecutive days) are not available for GAMMAPLEX 10%.

Preparation and Handling

  • GAMMAPLEX 10% is a clear or slightly opalescent, colorless or pale yellow liquid. Visually inspect parenteral drug products for particulate matter and discoloration prior to administration whenever solution and container permit. Do not use if the solution is cloudy or turbid, or if it contains particulate matter
  • GAMMAPLEX 10% vials are for single use only. Dispose of partially used or unused product
  • GAMMAPLEX 10% contains no antimicrobial preservatives. Therefore, prompt administration after preparation is necessary
  • Do not shake
  • Administer GAMMAPLEX 10% at room temperature (up to 25°C [77°F])
  • Do not use any solution that has been frozen [see How Supplied/ Storage and Handling (16)]
  • Infuse GAMMAPLEX 10% using a separate infusion line
  • Do not mix GAMMAPLEX 10% with other intravenous medications (including normal saline) or other IGIV products
  • An infusion pump may be used to control the rate of administration
  • For administration of large doses, pool multiple vials using aseptic technique


  • Hydrate the patient adequately prior to the initiation of infusion
  • Infuse GAMMAPLEX 10% intravenously using an intravenous infusion set. See Table 1 for recommended infusion rates
  • Monitor vital signs throughout the infusion
  • Slow or stop the infusion if adverse reactions occur
  • If symptoms subside, the infusion may be resumed at a lower rate that is comfortable for the patient
  • The observation time of patients after GAMMAPLEX 10% administration may vary. If the patient (a) has not received GAMMAPLEX 10% or another IgG product, (b) is switched from an alternative IGIV product or (c) has had a long interval since the previous infusion, prolong the observation time for adverse reactions after GAMMAPLEX 10% infusion
  • Certain severe adverse reactions may be related to the rate of infusion. Slowing or stopping the infusion often allows the reaction to disappear
  • Close monitoring of the infusion rate in pediatric patients is recommended
  • Ensure that patients with pre-existing renal insufficiency are not volume depleted
  • For patients at increased risk of renal dysfunction, thrombotic events, or volume overload, administer GAMMAPLEX 10% at the minimum infusion rate practicable. Consider discontinuing GAMMAPLEX 10% administration if renal function deteriorates [see Boxed Warning, Warnings and Precautions (5.1, 5.2, 5.8)]

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.