Effects of oral clarithromycin and amoxycillin on interdigestive gastrointestinal motility of patients with functional dyspepsia and Helicobacter pylori gastritis.
BACKGROUND
Clarithromycin and amoxycillin are antibiotics commonly used in association for Helicobacter pylori eradication. Because this treatment, which lasts 1-2 weeks, is frequently associated with gastrointestinal symptoms, we investigated the effects of these antibiotics on gastrointestinal motility.


METHODS
Gastroduodenal motility was recorded in 14 patients with functional dyspepsia and H. pylori gastritis by means of a low-compliance manometric system with four recording ports in the stomach and four in the duodenum. Two tablets of clarithromycin 250 mg (seven patients, clarithromycin group) or one of amoxycillin 1 g (seven patients, amoxycillin group), ground and dissolved in 20 mL of water, were given randomly and in double-blind manner 30 min after the end of the first activity front (AF) of the migrating motor complex (MMC) or, in the absence of AFs, after at least 200 min of recording. Recording continued until an AF was observed during the subsequent 200 min.


RESULTS
Clarithromycin administration was followed 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 was 48 min +/- 8.5 (mean +/- s.d.), significantly shorter than after amoxycillin (121 min +/- 29). The clarithromycin-related duodenal AFs showed 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 ones.


CONCLUSIONS
Clarithromycin stimulated cyclic gastroduodenal motility, while amoxycillin was ineffective. It is likely that symptoms during the eradication treatment are due to this effect of clarithromycin.
Bortolotti
M
M
Department of Internal Medicine and Gastroenterology, University of Bologna, Italy. mhbor@tin.it
Brunelli
F
F
Sarti
P
P
Mari
C
C
Miglioli
M
M
D000284:Administration, Oral; D000328:Adult; D000658:Amoxicillin / Q000009:adverse effects / Q000494:pharmacology*; D017291:Clarithromycin / Q000009:adverse effects / Q000494:pharmacology*; D004311:Double-Blind Method; D004359:Drug Therapy, Combination / Q000009:adverse effects / Q000494:pharmacology*; D004415:Dyspepsia / Q000139:chemically induced*; D005260:Female; D005769:Gastrointestinal Motility / Q000187:drug effects*; D016481:Helicobacter Infections / Q000188:drug therapy* / Q000503:physiopathology; D016480:Helicobacter pylori; D006801:Humans; D008297:Male; D008875:Middle Aged
D000658:Amoxicillin; D017291:Clarithromycin