We report 22 cases of prepubertal gynecomastia diagnosed during growth
hormone (GH) treatment. The age and dose range were 2 to 12 years and
1.8 to 0.3 mg/kg per week, respectively. In most of the patients, gyn
ecomastia appeared between 0.5 and 7 months after GH was started. Thre
e boys were using drugs other than GH. This condition appears to be se
lf-limited and benign.