Comparison of Effect of Fasting and of Five Different Diets on the Bioavailability of Single Oral Dose of Amoxicillin 500 mg Capsule

The objective of this crossover bioavailability study on amoxicillin was to compare the bioavailability under fasting and five different diets, in twelve healthy adult male human volunteers. A single dose of amoxicillin 500 mg capsule was administered at six occasions: after overnight fasting, after two vegetarian diets (high-fat and low-fat), two non-vegetarian diets (high-fat and low-fat) and milk. Serial blood samples were collected up to 8 h after dose. Plasma concentrations were determined using a validated LC-MS/MS method. Tmax increased and AUC and Cmax values decreased in the presence of food. The non-vegetarian diets affected the rate of absorption of amoxicillin more than the vegetarian diets.