GASTROINTESTINAL TRANSIT OF AMOXICILLIN MODIFIED-RELEASE TABLETS AND A PLACEBO TABLET INCLUDING PHARMACOKINETIC ASSESSMENTS OF AMOXICILLIN

Background: We have investigated the gastrointestinal transit time of, the influence of food intake on, the disintegration of, and the pharm acokinetics of amoxicillin in a modified-release form. Methods: Radiol abelled modified-release tablets of amoxicillin and placebo tablets we re administered, in an open three-way, randomized, crossover design, a s single doses during omeprazole treatment, to six male healthy subjec ts during fasting and non-fasting conditions. Radioscintigraphic image s and plasma samples were obtained. Results: The estimated mean (and r ange) gastric emptying time of the modified-release tablet after drug administration was 0.3 h (0.1-1.0 h) during fasting conditions, 4.3 h (1.7-5.0 h) after a light breakfast, and 4.9 h (1.9-18.0 h) after a he avy breakfast. The small-intestinal transit time during fasting condit ions was 4.7 h (2.9-6.9 h) and was not significantly changed after lig ht or heavy breakfast intake. The relative bioavailability of the modi fied-release tablet was 55%, compared with a commercially available am oxicillin immediate-release tablet. Conclusion: The modified-release t ablet of amoxicillin administered postprandially apparently increases the amoxicillin release time in the stomach. The relevance of its use for anti-H. pylori treatment can be questioned.