[Effect of phloroglucinol on rectosigmoid motility stimulated by a test meal. Study in patients with irritable bowel syndrome].

Twenty patients (15 women, 5 men, mean age: 46.3 +/- 11.82 years, mean weight: 70.9 +/- 8.83 kg) presenting with a 8.5 +/- 4.7 years' history of irritable bowel syndrome associated predominantly with postprandial abdominal pain were recruited into the study. They underwent, after an enema, a rectosigmoid manometry (4 channels, low compliant infusion pump and catheters) before and after a 1000 kcal standardized meal. At the end of the meal they were administered intravenously phloroglucinol (two 40 mg ampoules) or placebo (two ampoules). Both treatments were strictly similar and the order of administration was randomly assigned Motor activity at the rectum, rectosigmoid, lower sigmoid and sigmoid level was determined using a motor index calculated for each 15 min period. Three preprandial and four postprandial indices were calculated. Both groups were statistically similar for sex ratio, age and history of disease. A slight difference was noted for mean weight: the caloric instake per kg of weight was a little higher in the phloroglucinol group. Mean preprandial indices were comparable in both groups. Variance analysis showed that the increase in postprandial motor indices was statistically less pronounced in the phloroglucinol group than in the placebo group. In the placebo group a clear cut increase in motor activity was assessed, which was not observed in the phloroglucinol group. This variation of motricity, which was observed at every level, was more pronounced for the first two postprandial indices than for the last two ones. These results suggest that phloroglucinol is able to reduce rectosigmoid motor response after a test meal. This could explain its activity in abdominal pain associated with irritable bowel syndrome.