List of products in the National Drug Code with proprietary name . This medication is used to treat a certain blood disorder (idiopathic thrombocytopenia purpura - ITP) in which the blood does not clot properly due to a lack of platelets. Platelets are a type of blood cell needed to form blood clots and prevent bleeding. Romiplostim decreases your risk of bleeding by increasing the number of platelets. Romiplostim acts like a certain natural substance (thrombopoietin) that causes the body to produce platelets.