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Background. Intravenous immunoglobulin (IVIG), a pooled blood product acquired from multiple healthy donors, is an effective treatment for various types of autoimmune diseases, haematological disorders, and infectious diseases. Adverse haematological events such as throm-bocytopenia are rarely caused by IVIG. Objectives. To investigate the phenomenon of IVIG-induced thrombocytopenia. Materials & Methods. A case study and a review of the previous literature based on a search using MEDLINE (PubMed) and ICHUSHI (for Japanese literature) electronic databases. Results. The present case of dermatomyositis exhibited two episodes of IVIG-induced thrombocytopenia, which occurred a few days after initiating IVIG and was significant within two weeks without haemorrhagic symptoms. Spontaneous remission of thrombocytopenia was repeatedly observed. Based on a review of five cases, the underlying disorders were autoimmune bullous diseases in three of the five cases. Polyethylene glycol-treated human immunoglobulin products were used in three of the five cases. The clinical course of IVIG-induced thrombocytopenia was similar to that in our present case. Conclusion. Because of the rarity of severe haemorrhagic symptoms and spontaneous remission of IVIG-induced thrombocytopenia, discontinuation of IVIG due to thrombocytopenia is not straightforward.