Evaluation of effect of food ingestion on bioavailability of cephalexin by moment analysis.

The effect of food ingestion on the bioavailability of cephalexin in humans was investigated. The amounts of urinary excretion following single oral doses to healthy male subjects were determined by high-performance liquid chromatography, and the bioavailability was evaluated by means of moment analysis of excretion rate-time curves. The ingestion of test meals (high carbohydrate, high protein and high fat) delayed the excretion rate with the peaks approximately two-thirds lower and 1-1.5 hr later than that in fasting subjects, but did not affect the total excretion amounts. No significant difference was found among the test meals. The moment analysis indicated that the rate of bioavailability increased by an average of 71% following food ingestion without significant change in the extent of bioavailability.