Effect of pirenzepine on oesophageal, gastric, and enteric motor function in man

The effect of pirenzepine on oesophageal, gastric, and enteric motor function was evaluated in six healthy volunteers. Each subject was studied before and after taking pirenzepine, 100 mg/day, for 3 days. Half and complete gastric emptying times of clear liquid, assessed by epigastric impedance, were significantly delayed by the drug: 6.16 +/- 1.74 min and 13.8 +/- 4.64 min versus 16.65 +/- 3.03 min and 25.1 +/- 8.2 min, respectively (p less than 0.05). Enteric motility was assessed by manometry, and variables studied were the duration of the various phases of the migratory motility complex, the frequency of contractions in phase III, and the amplitude of contractions in phases II, III, and in the postprandial period. Only phase I was affected and was significantly prolonged by the drug: 16.08 +/- 5.94 min versus 31.65 +/- 12.88 min (p less than 0.01). Oesophageal motility was assessed by manometry. Variables studied were amplitude and duration of contractions in the body of the oesophagus, and lower oesophageal sphincter pressure. Results were not significantly changed by the drug. We conclude that pirenzepine, given at a dose used for treatment of peptic ulcer disease, significantly delays the gastric emptying of liquids, has minimal effect on enteric motility, and has no effect on oesophageal motility. The effect on gastric emptying may be therapeutically useful by reducing the acid load on the duodenum in duodenal ulcer disease.