Effect Of Hsr-903, A New Fluoroquinolone, On The Concentration Of Theophylline In Serum

The effect of HSR-903, a new fluoroquinolone, on the concentration of theophylline in serum in healthy male volunteers was investigated. The concentration of theophylline in serum and the urinary excretion rates of theophylline on day 5 of concomitant dosing with HSR-903 tended to increase compared to those on day 4, when theophylline was given alone; however, the urinary excretion rates of 1-methyluric acid and 3-methylxanthine on day 5 of concomitant dosing with HSR-903 tended to decrease in comparison to those on day 4, when theophylline,vas given alone.