Effect of atropine and upper gastrointestinal endoscopy on serum gastrin.

To determine if atropine alone, gastric distension alone, or atropine plus gastric distension affected serum gastrin levels, we obtained serum gastrins on 45 consecutive patients who were randomized into two groups. Group 1 (27 patients) was premedicated with meperidine alone, 1.5 mg/kg I.M. Group 2 received atropine 0.6 mg I.M. in addition to meperidine. Blood samples were drawn: 1) before premedication, 2) 30 minutes after premedication, and 3) immediately after endoscopy. We found: 1) no statistical difference between mean basal gastrin levels for groups 1 and 2, 2) no change in basal serum gastrin levels after premedications in either group, and 3) that endoscopy caused no significant increase in mean serum gastrin levels. We conclude that endoscopy does not lead to a significant elevation of basal serum gastrin in patients premedicated with meperidine or meperidine and atropine.