Intravenous immunoglobulin (IVIg) has been found to have a multitude of uses. However, IVIg is a pooled blood product and as a result a limited resource. At replacement doses (200-400 mg/kg/month) it is of critical utility in the treatment of primary and secondary antibody deficiencies. High-dose immunoglobulin (hdIVIg) given at doses of up to 2 g/kg/day has immunomodulatory action mediated via a number of different effects. First used in the 1980s for the treatment of idiopathic thrombocytopenic purpura, hdIVIg has found uses in a wide range of autoimmune conditions, though for many conditions the evidence base lacks formal randomized controlled trials (RCTs). This article will detail the issues regarding the manufacture and clinical aspects of administration of hdIVIg and its uses, especially with regards to the treatment of autoimmune disease.