Lupron stops the pituitary gland from producing Luteining Hormone (LH) and Follicle Stimulating Hormone (FSH). In turn, that will stop the testicles (in boys) from producing testosterone, if they are undergoing true puberty.

A large amount of testosterone from the testicles will have the effect of speeding up your child’s growth and advancing his bone age. Therefore, if the Lupron was discontinued and your son was undergoing true puberty, that could explain the rapid growth and advanced bone age.

Usually, if a child is found to need the Lupron, s/he is kept on it till an age when s/he would normally undergo puberty....or until bone age and chronological age roughly match up.