INHALED FLUTICASONE PROPIONATE - A REVIEW OF ITS PHARMACODYNAMIC AND PHARMACOKINETIC PROPERTIES, AND THERAPEUTIC USE IN ASTHMA

Fluticasone propionate is an androstane carbothioate glucocorticostero id with almost twice the topical anti-inflammatory potency of beclomet hasone dipropionate. Importantly, it is not appreciably absorbed from the gastrointestinal tract. However, the fraction of active drug absor bed from the lungs after inhalation, and therefore total systemic avai lability has yet to be determined. Inhaled fluticasone propionate admi nistered at dosages of 1500 mu g/day for 1 year or 2000 mu g/day for 6 weeks did not cause clinically significant pituitary-adrenal suppress ion. Preliminary data from 2 published trials also indicate no signifi cant effect on growth in children. However wider clinical experience i s needed to clarify the effects of long term administration on pituita ry-adrenal function, bone metabolism and attainment of adult height in children. In clinical studies, inhaled fluticasone propionate was at least as effective as beclomethasone dipropionate or budesonide when a dministered at half the dosage of the comparators in patients with mil d to moderate or severe asthma. Limited data suggest that fluticasone propionate also has considerable potential in the management of childh ood asthma. In trials of up to 1 year in duration, fluticasone propion ate appeared to be well tolerated by both adults and children. Whether an improved tolerability profile compared with other corticosteroids is a major clinical benefit of the extremely low oral bioavailability of inhaled fluticasone propionate requires confirmation. Nevertheless, on the basis of available data from initial clinical trials of mostly limited duration, inhaled fluticasone propionate offers an effective treatment option for the management of asthma, with the potential of a n enhanced safety profile.