12/13/2012
Does the AAAAI have any guidelines or position on dosing IVIG on actual vs ideal body weight? Based on the pharmacokinetic profile and distribution characteristics, dosing with ideal body seems to make sense, and many institutions around the country do this. I would be very interested in an opinion. Thanks very much.

Thank you for your inquiry.

The AAAAI does not have a position regarding your question, but I am sending your inquiry to Dr. Mark Ballow, who is a nationally known expert in treatment of immunodeficiency disorders including the administration of immunoglobulin replacement therapy. As soon as we hear from Dr. Ballow, we will forward his response to you.

Thank you again for your inquiry.

Sincerely,
Phil Lieberman, M.D.

We have received a response from Dr. Mark Ballow regarding your Ask the Expert question. Thank you again for your inquiry and we hope this response is helpful to you.

Sincerely,
Phil Lieberman, M.D.

Response from Dr. Mark Ballow:
I am not aware of any recommendations for IVIG dosing for ideal vs actual weight. The more important variable is the clinical response. It is reasonable to start with ideal weight but the dose may have to be adjusted to control infections - the biologic trough level. A paper by Berger et al (Clin Immunology 139:133, 2011) reported bioavailability of SCIg and showed that obese individuals had bioavailability correction factors higher than individuals with normal BMI. However, he concluded that the mean dose adjustment should only be rough guides and each patient's optimal IgG level and dose should be determined individually by their clinical response. Another article (editorial) that might be of interest is that by Bonilla (Clin Immunology 2011).

Mark Ballow