The effect of single doses of inhaled beclomethasone dipropionate on the circadian rhythm in serum osteocalcin in normals.

A single dose of 2.5 mg prednisone leads to a significant transient decrease in serum osteocalcin, which is only demonstrated by frequent serum sampling. The aim of the present study was to evaluate whether a single dose of inhaled beclomethasone dipropionate causes transient changes in serum osteocalcin, indicating a systemic effect on bone cells. In a double-blind, placebo controlled, cross-over design we evaluated the effects of single doses of 250 micrograms and 1000 micrograms beclomethasone on the circadian rhythm in serum osteocalcin. Fifteen normal subjects aged 23-38 years were studied twice with an interval of one week with hourly blood sampling from 16.30 until 17.00 the following day; 1000 micrograms beclomethasone, but not 250 micrograms, suppressed serum cortisol by 14.4 +/- 6.7% (p = 0.03). Neither of the beclomethasone doses significantly altered the time pattern of serum osteocalcin. We conclude that a single inhaled dose of beclomethasone in the therapeutical range does not acutely influence osteoblastic activity as judged from serial measurements of serum osteocalcin.