The efficacy and side effects of hydroxyurea in young children with sickle
cell disease are unknown. The authors followed-up eight young children (mea
n age 3.7 years) during therapy with hydroxyurea for an average of 137 week
s. Total and fetal hemoglobin levels rose with hydroxyurea therapy. Hospita
l admission rates and total hospital days decreased during hydroxyurea ther
apy. No unexpected toxicity occurred, and growth and development were unaff
ected. This pilot study suggests that hydroxyurea is safe and effective in
young children with sickle cell disease.