Primary immune thrombocytopenia (ITP)--formerly known as idiopathic thrombocytopenic purpura--is an autoimmune disorder characterized by immune mediated thrombocytopenia. The aetiology of ITP remains unknown, but studies have shown that multiple immunological mechanisms are involved in the pathogenesis of ITP. This article aims to provide an overview of current treatment options, with particular emphasis on new biological therapies: rituximab, a monoclonal anti-CD20 antibody, and the thrombopoietin receptor agonists romiplostim and eltrombopag.