Normal platelet counts are 150,000 to 450,000 per microliter in circulating blood. Platelet counts that drop below 20,000 require treatment and hospitalization. ITP treatment includes medication to block antibodies that are attacking platelets. In some cases medication is needed to block antibody production in the body. For cases where the spleen is enlarged, surgery may be required to remove the organ. Severe bleeding will require blood transfusions to replace blood that is lost, and platelet concentrates may be given in severe cases.