Adrenocortical function after chronic inhalation of fluocortinbutyl and beclomethasone dipropionate

Abstract

Fluocortinbutyl (FCB) is a C-21 ester, topically active corticosteroid; no adrenal suppression was noted after large doses. Safety and effects on adrenocortical function of orally inhaled FCB (40 mg/day), beclomethasone dipropionate (BDP) (2 mg/day) and placebo administered in 4 monitored divided doses for 4 wk by 3 groups of 5 healthy men were compared. Circadian plasma cortisol concentrations and daily urinary free cortisol excretion were determined before and after 3 and 4 wk exposure. Although pretreatment mean area under the curve (.mu.g.cntdot.h.cntdot.dl) for plasma cortisol did not differ among groups, mean values after weeks 3 and 4 of treatment were lower (P < 0.05) in the BDP group (95.1 and 83) than in the FCB (155.8 and 153.7) and placebo (141 and 135.8) groups. Mean urinary cortisol excretion after wk 4 for the BDP group (29 .mu.g) was less (P < 0.05) than in the FCB (59 .mu.g) and the placebo (69 .mu.g) groups. Slopes of individual regression lines noting time trends in plasma and urinary cortisol in the BDP group were negative and less (P < 0.05) than those of the other groups. A cosyntropin test given i.v. after 4 wk of exposure caused similar plasma cortisol responses among groups. No serious adverse effects were noted. After long-term high-dose treatment BDP but not FCB suppressed basal adrenocortical function, but neither suppressed the adrenocortical response to cosyntropin. [FCB and BDP are used to treat asthma.].