Acceleration of Delayed Growth With Fluoxymesterone

61 boys with constitutional delay of growth and maturation, aged 9-19 years and with a bone age (BA) lag of 1.3-5.5 years, were administered fluoxymesterone (0.05-0.24 mg/kg daily orally, relative dose increasing with age) to accelerate growth. The therapy was continuous and lasted 0.4-3.6 years. The findings are compared with 37 observation periods in a similar group of untreated boys. Growth velocity increased in every treated boy during the therapy, the mean first-year increment being 4.3 +/- 1.6 cm/year. For most boys this brought about a decrease in the height difference from peers, and so afforded the psychosocial relief that was the objective of the therapy. After therapy the velocity decreased slightly in most boys, from a mean of 9.1 +/- 1.4 to 7.1 +/- 3.3 cm/year. The effect of the intervention on final height was assessed by three relatively independent methods of prediction. These were found to be equally valid in the 15 control boys for whom final heights are known. The effect appeared to vary individually, but on the average there appeared to be no loss of height potential. No individual boy with initial BA greater than 10.5 years showed a substantial reduction in predicted final height.