In children, the outlook for acute ITP is generally very good. About 75% of patients recover completely within three months, and about 80% recover within six months. Less than 1% of children with ITP develop bleeding within the skull. Only a small percentage of children go on to develop chronic ITP, and most of these children do not have serious bleeding.
Symptoms of chronic ITP usually come and go in adults. When medication is necessary, about 50% of patients who are treated with prednisone have normal platelet counts within four to six weeks. However, when the prednisone is reduced, the platelet count drops again in many people. If this happens, doctors may recommend that the person's spleen be removed. Within one week of having the spleen removed, about 70% of adult patients with chronic ITP have normal platelet counts. The risk of removing the spleen is an increased risk of infections.