Steroids & surgery. Many cases of itp resolve with supportive care and corticosteroid treatment. In resistant cases, spleen, the site of platelet destruction, may be removed.
Many options. If you have no symptoms, waiting can sometimes be an option. Ivig, winrho (if you are rh (+)) or steroids (once you have ruled out malignancy as the cause for low platelets) can be used. If these are unsuccessful, potent immunosuppressives can be considered such as vincristine or rituximab. Splenectomy can also be considered for someone who is refractory to medical intervention.