To determine the influence of sucralfate on the absorption of erythromycin, prior to evaluating its efficacy in decreasing erythromycin-associated gastrointestinal (GI) intolerance, we assessed pharmacokinetic parameters in six healthy adult volunteers. Erythromycin ethylsuccinate administered alone or with sucralfate as a single dose was compared. Sucralfate did not significantly alter the elimination rate constant, half-life, or area under the curve for erythromycin ethylsuccinate. It is therefore unlikely that efficacy of erythromycin ethylsuccinate will be altered when sucralfate is coadministered.