Intravenous immunoglobulins (IVIgs) are used increasingly as therapy for neuroimmunologic and other autoimmune diseases. With broader use, the number of reported side effects also is growing. Here we review the literature on adverse reactions reported after administration of i.v.Igs. Despite a few recent reports about a high frequency of complications of IVIgs, by and large they can be considered as safe. Mild and self-limited side effects may occur, but severe complications are rare and often associated with other risk factors for these complications. A careful screening for preexisting illnesses and monitoring of some laboratory parameters can minimize the risks of IVIg therapy.