Effects of dairy products on the oral bioavailability of moxifloxacin, a novel 8-methoxyfluoroquinolone, in healthy volunteers.

OBJECTIVE: To investigate the effect of concomitant administration of dairy products on the pharmacokinetics and tolerability of moxifloxacin. DESIGN: This was a single-centre, randomised, controlled, nonblinded, 2-way crossover study in healthy volunteers. PARTICIPANTS: 12 healthy men (aged 25 to 46 years) were enrolled in the study. METHODS: The plasma and urinary pharmacokinetics of moxifloxacin were investigated after single doses of moxifloxacin 400mg administered orally either under fasting conditions or immediately after 250g of yoghurt that was to be consumed within 15 minutes. There was a 1-week interval between the study periods. RESULTS: Administration of moxifloxacin after yoghurt had no effect on the extent of absorption, as estimated by the area under the plasma concentration-time curve from zero to infinity [AUCinfinty; geometric means 31.8 versus 33.9 mg/L x h after test and reference, respectively; estimated true treatment ratio 94%, 90% confidence interval (CI) 90 to 98%]. The rate of absorption was slightly decreased, with a slight reduction in maximum plasma concentration (Cmax; geometric means 2.44 versus 2.87 mg/L; estimated true treatment ratio 85%, 90% CI 74 to 98%) and a prolonged time to reach Cmax (tmax; median 2.75 versus 0.88 hours). The treatments were well tolerated in these healthy individuals. CONCLUSIONS: The effects of yoghurt on the pharmacokinetics of moxitloxacin are considered not clinically relevant. Hence, no special recommendations for administration are required when moxifloxacin is given together with dairy products.