Of 100 consecutive patients referred for antroduodenal manometry, we successfully intubated 89 with endoscopic and/or fluoroscopic guidance. In 8 of 8 patients who had failed with our usual techniques, we infused erythromycin 3 mg/kg i.v. over 1 h, and the tube moved through the pylorus and into the duodenum. Erythromycin, which stimulates propagation of 3 high amplitude antral contractions/min, appears to be a safe, noninvasive means to facilitate the postpyloric passage of tubes.