Hydroxyurea for the treatment of sickle cell disease.

HU is efficacious in children and adults with SCD; with an increase in Hb F%, and reduction in hospitalizations and pain crises. However, few studies have measured the effectiveness of HU for SCD in usual practice. The paucity of long-term studies limits conclusions about toxicities and about mortality. Future studies of interventions to overcome the barriers to use of HU in patients with SCD are necessary.