EFFECTS OF ORAL CLARITHROMYCIN AND AMOXICILLIN ON INTERDIGESTIVE GASTROINTESTINAL MOTILITY OF PATIENTS WITH FUNCTIONAL DYSPEPSIA AND HELICOBACTER-PYLORI GASTRITIS

Background: Clarithromycin and amoxycillin are antibiotics commonly us ed in association for Helicobacter pylori eradication. Because this tr eatment, which lasts 1-2 weeks, is frequently associated with gastroin testinal symptoms, we investigated the effects of these antibiotics on gastrointestinal motility. Patients and methods: Gastroduodenal motil ity was recorded; in 14 patients with functional dyspepsia and H. pylo ri gastritis by means of a low-compliance manometric system with four recording ports in the stomach and four in the duodenum. Two tablets o f clarithromycin 250 mg (seven patients, clarithromycin group) or one of amoxycillin Ig (seven patients, amoxycillin group), ground and diss olved in 20 mt of water, were given randomly and in double-blind manne r 30 min after the end of the first activity front (AF) of the migrati ng motor complex (MMC) or, in the absence of AFs, after at least 200 m in of recording. Recording continued until an. AF was observed during the subsequent 200 min. Results: Clarithromycin administration was fol lowed by a typical gastroduodenal AF in a significantly higher number of patients than for amoxycillin administration. In addition, the time lag between clarithromycin administration and the appearance of AFs w as 48 min +/- 8.5 (mean +/- s.d.), significantly shorter than after am oxycillin (121 min +/- 29). The clarithromycin-related duodenal AFs sh owed a duration of 6.6 min +/- 1.5, significantly longer than that of the spontaneous AFs (3.6 min +/- 1.2, P < 0.01), while the amoxycillin -related AFs were not significantly different from the spontaneous one s. Conclusion: Clarithromycin stimulated cyclic gastroduodenal motilit y, while amoxycillin was ineffective. It is likely that symptoms durin g the eradication treatment are due to this effect of clarithromycin.