Therapeutic utilization of the diurnal variation in pituitary-adrenocortical activity.

The degree of pituitary-adrenocortical suppression resulting from exogenous corticosteroid is related to the time of day the steroid is administered. Morning administration has less effect and evening administration a greater effect than do divided doses given over the course of the day. Clinical studies have shown that in the great majority of patients with corticosteroid responsive diseases, an intermittent dosage schedule is at least as effective as is administration of an equal dose in a three or four times a day regimen. Other undesirable side effects of corticosteroid therapy may also be decreased by an intermittent schedule. It is suggested that the customary divided dosage schedule for corticosteroid administration be replaced with an intermittent regimen, the medication being given in the morning. This may be once a day, or, if therapeutic results are satisfactory, once every other day.