You should be tested for IgG, (including all four subclasses), IgM, IgA and also IgE...to see if you are truly deficient in any or all of these categories. If so, then I think the better course would be to replace them with IVIG...which would be immediately approved if you are shown to be deficient. This will not only help your immune system, but you will get the added benefit of the KNOWN and studied improvement of your SFN with IVIG.