We assessed the immediate effect of intravenous immunoglobulins (IVIG) on the biochemical, immunological and hematological profiles in patients with hypogammaglobulinemia. Over a period of three months, patients with antibody deficiencies, who had been established on stable IVIG treatment as replacement therapy in our hospital, were enrolled in the study. Participants underwent pre-therapy determinations of their biochemical, immunological and hematological profiles. Laboratory determinations were repeated after completion of IVIG infusions. Over the study period, fourteen patients were enrolled and a total of 34 pre- and post-IVIG infusion determinations were performed and results compared. We found that low-dose IVIG treatment in patients with hypogammaglobulinemia results in post-infusion biochemical and hematological changes, as follows: an increase in total protein concentration and a reduction in albumin, total cholesterol, sodium and alkaline phosphatase concentrations as well as lymphocyte and platelet counts. All these biochemical and cellular changes seems to be transient, since they were not observed in the subsequent pre-infusion determination. However, in other patient populations, some of these changes might differ, depending on the dose of IVIG administered and the baseline condition and immunological status of the patient.