Effect of hyoscine butylbromide on gastroesophageal reflux in barium studies of the upper gastrointestinal tract.

Hyoscine butylbromide (Buscopan) is an intravenously administered hypotonic agent that significantly reduces pressure in the lower esophageal sphincter and may therefore artificially induce gastroesophageal reflux during barium examination of the upper gastrointestinal tract. This study was performed to test this hypothesis. The presence or absence and severity of gastroesophageal reflux before and after intravenous injection of 20 mg Buscopan were evaluated in 112 consecutive patients undergoing biphasic upper gastrointestinal examination. Gastroesophageal reflux was seen in 49 (44%) of the patients. Reflux was evident both before and after the injection of Buscopan in 35 (31%) of the patients, before injection only in 10 (9%) and after injection only in 4 (4%). The magnitude of reflux after injection of Buscopan was reduced or the same in 108 of the patients (96%) and increased in 4 (4%). There was no significant difference in the overall occurrence (p = 0.41) or degree (p = 0.81) of gastroesophageal reflux before and after injection of Buscopan (chi 2 test). The authors conclude that the routine use of Buscopan is unlikely to spuriously increase the frequency or degree of gastroesophageal reflux observed on upper gastrointestinal barium studies.