WHICH FORM OF ERYTHROMYCIN SHOULD BE USED TO TREAT GASTROPARESIS - A PHARMACOKINETIC ANALYSIS

Background: Erythromycin is a macrolide antibiotic that exhibits proki netic effects, It has been shown to enhance antral contractility and a ccelerates gastric emptying rates, primarily by stimulating motilin re ceptors, Aim: To determine the optimal dosage form of erythromycin for use as a prokinetic agent. Methods: Eight normal volunteers and three patients with documented gastroparesis ingested 250 mg erythromycin i n tablet, suspension and intravenous forms, Serum erythromycin levels were determined at frequent intervals, These data were plotted vs. tim e and analysed for lag time, time to maximum concentration (t(max)), m aximum concentration (C-max) and bioavailability (F). Results: The abs orption kinetics of the erythromycin suspension was notable for short lag times and early t(max), while lag times and t(max) were delayed wi th the tablet form. Median lag time was 15 min for the suspension vs, 90 min for the tablet (P < 0.005). Median t(max) for the suspension wa s 45 min vs, 180 min for the tablet (P < 0.005), A non-significant dec rease in F was seen with the suspension compared to the tablet (P = 0. 12). Conclusion: Based on the kinetic data from this study, erythromyc in suspension is the ideal dosage form for administration of this drug as a prokinetic agent.