The effect of danazol in sexual precocity.

The effect of Danazol, a synthetic 2,3 isoxazol derivative of 17 alpha-ethinyl testosterone, was assessed in three girls and two boys with sexual precocity. Progression of sexual development ceased during administration of Danazol; the effect upon growth rate and skeletal maturation was equivocal. Serum estrogen and progesterone concentrations in the girls were lower during treatment; serum testosterone and dehydroepiandrosterone levels in the boys were also lower. Serum and urinary luteinizing hormone concentrations were inconsistently suppressed. No effect upon follicle-stimulating hormone levels could be demonstrated. Although Danazol appears to inhibit sexual development, this study indicates that the pituitary-gonadal axis is not completely suppressed. Growth rate is not reverted to normal, and virilization may occur among girls. Because undesirable side effects may outweight desirable results, careful consideration is recommended before Danazol is prescribed in the management of sexual precocity.