Data from the McKenzie vasoconstrictor assay in man are consistent with these results. The precise mechanisms of fluticasone propionate action in asthma are unknown.
Inflammation is recognized as an important component in the pathogenesis of asthma.
These anti-inflammatory actions of corticosteroids may contribute to their efficacy in asthma. Though highly effective for the treatment of asthma, corticosteroids do not affect asthma symptoms immediately. However, improvement following inhaled administration of fluticasone propionate can occur within 24 hours of beginning treatment, although maximum benefit may not be achieved for 1 to 2 weeks or longer after starting treatment. When corticosteroids are discontinued, asthma stability may persist for several days or longer. The activity of fluticasone propionate inhalation powder and aerosol is due to the parent drug, fluticasone propionate.