Immunoglobulin concentrates being administered intravenously should be infused carefully to minimize adverse effects.
Some intravenous dosage regimens:
(1) congenital immunoglobulin deficiency: 200- 800 mg/kg per month
(2) ITP: 400 mg/kg/day for 2-5 days, or 1 g/kg/day for 1-2 days
maximum immunoglobulin infusion rate =
= 5 mg per kg per minute
maximal hourly infusion rate for an immunoglobulin solution in mL/h =
= (maximum infusion rate in mg/kg/min) * (body weight in kilograms) * (60 min/h) / (1000 * (percent immunoglobulin in preparation))
where:
• The percent immunoglobulin is entered as decimal fraction from 0 to 1, or as (percent from 0 to 100)/100.
• The range of immunoglobulin concentrations is from 3% to 12%.
• The 1,000 is for converting mg to grams.
• An X% immunoglobulin solution has X grams immunoglobulin in 100 mL solution.
Infusion:
(1) The infusion rate for the first 30 minutes is 25% of the maximal rate.
(2) The infusion rate for the second 30 minutes is 50% of the maximal rate.
(3) After the first hour, the infusion can be increased to the full rate.
amount given in first hour in grams =
= 0.375 * (maximal hourly infusion rate in mL/h) * (percent concentrate as grams/dL)
number of additional hours to infuse =
= ((total dose in grams) – (amount given in first hour)) / ((maximal infusion rate) * (percent concentrate in grams/dL)
total number of hours for infusion =
= (number of additional hours) + 1
Specialty: Clinical Laboratory, Immunology/Rheumatology