My 12 month old daughter's iga and igg levels are low. is this serious and what are the treatments?

It depends: The most important thing is your daughter's history. If she is healthy, the levels are probably low because her immune system is a little slow developing. If she is sick more than the average child (3-8 infections per year) or has unusually severe infections, she may have a clinical immune deficiency. If so, she can be treated with Immune Globulin and/or prophylactic antibiotics. See immunologist.

See an immunologist: The levels might not be low for her age, normal levels depend on specific age. If they are truly low, it might be a transient deficiency that could resolve with time, or she may have an immunodeficiency.