OXANDROLONE EFFECT ON GROWTH AND BONE AGE IN IDIOPATHIC GROWTH FAILURE

Abstract

ABSTRACT Oxandrolone, an anabolic steroid, administered to patients with idiopathic growth failure in a dosage of 0.15-0.25 mg/kg·day, significantly stimulates immediate growth during the first 6 months of treatment and results in a greater height age Δ than bone age Δ during this interval. In 9 patients continued for an additional 6 months, average cumulative 12 months values for corrected height age Δ and bone age Δ were approximately equal and almost double those of 50th percentile normals. These data during 12 months of continuous oxandrolone therapy suggest that the drug can increase immediate stature, but has no net effect on ultimate predicted stature. Similar results were noted in 2 patients treated continuously for 24 months. If treatment is discontinued after 6 months, growth velocity and corrected height age Δ, but not bone age Δ, decrease significantly during the next 6 months. Cumulative results in patients treated intermittently over 12 months shows that bone age Δ exceeded corrected height age Δ by 3 or more months in 4 out of 9 patients, indicating an unfavourable effect on predicted ultimate stature in such instances. Therefore, oxandrolone administration for the purpose of increasing immediate stature should probably be given continuously until mid-puberty is reached, except in those patients showing an unfavourable response during the first 6 months of treatment. At the present time, there is no reliable criterion for picking out those patients who will respond best to the drug, except by a 6 month trial of therapy. The drug appears safe; there are a small percentage of patients who have reversible changes in serum transaminase levels on therapy; mild virilization was noted in one patient. Careful monitoring of bone age at 6 months intervals and liver function at 3 months intervals is recommended during the period of treatment.