Introduction. Intravenous immunoglobulin G (IVIG) is a blood product from polyvalent and polyclonal immunoglobulin G. It covers a broad range of indications as immunomodulator or replacement therapy. In addition, although it is considered a safe therapy, the incidence of adverse reactions reported in the bibliography ranges from 1 % to 81 %. The objective of this study was to assess IVIG use and describe related adverse events in a tertiary care children's hospital. Population and methods. This was a pharmacoepidemiological, observational, and prospective study. Patients receiving IVIG for 7 months in 6 areas of a tertiary care children's hospital in the Autonomous City of Buenos Aires were assessed. The analysis unit was each IVIG infusion, and the main variable was the presence of adverse reactions. Results. A total of 305 infusions in 111 patients were analyzed. In 81.6 % of cases, the indication was for replacement. The maximum dose was 1 g/kg. In 99.6 % of infusions, some type of premedication was indicated; diphenhydramine was the most common drug, with varying dosages. A total of 12 adverse reactions (3.9 % of infusions) were recorded; 3 were severe: aseptic meningitis (2 cases) and seizures (1 case). All resolved to normal. Conclusions. The rate of IVIG adverse reactions in our setting was low; most reactions were mild and immediate and resolved favorably in all patients.