Effect on bone growth of daily versus alternate-day corticosteroid administration: an experimental study.

Young rabbits that received large doses of corticosteroids on an alternate-day basis grew normally and showed muscle and bone turnover patterns indistinguishable from those of untreated animals. In contrast, the daily administration of corticosteroids profoundly affected the skeletal system: growth ceased, and there were marked narrowing and premature closure of the epiphyseal plates. Osteoporotic changes were present at 1 week and progressed during the next 9 weeks. Muscle atrophy occurred early in the course of treatment and was associated with increased muscle fat deposition. Thus, in this study, alternate-day administration of corticosteroids clearly lessened the corticosteroid side effects of growth retardation, osteoporosis, and muscle wasting.