The tendency of a gelatin capsule to lodge in the esophagus, dissolve, and release its contents, as a potential etiology of drug-induced esophageal injury, was studied in 18 asymptomatic volunteers. Their ages ranged from 21 to 81 years, with nine subjects over 70 years old. Esophageal transit time of liquids was measured in all subjects after which the esophageal transit time of a #00 gelatin capsule containing technetium (99mTc) sulfur colloid was measured with a 120 ml and a 15 ml water bolus. The capsule lodged in three subjects (17 percent) with the 120 ml bolus and in 11 subjects (61 percent) with the 15 ml bolus. Esophageal manometry demonstrated a lower mean amplitude of esophageal contractions in subjects in whom the capsule lodged with the 120 ml bolus and in the elderly subjects. We conclude that the esophageal transit time of a gelatin capsule is related to the volume of fluid chaser. Our findings that a lower amplitude of esophageal contractions was associated with elderly patients and those in whom the capsule lodged with the large fluid bolus are worthy of further investigation.