Otilonium bromide enhances sensory thresholds of volume and pressure in patients with irritable bowel syndrome.

Visceral hyperalgesia has been suggested to play a role in the development of symptoms presented by irritable bowel syndrome patients. Otilonium bromide was developed to block smooth muscle Ca release to control cramping pain of these patients. Aims: to determine whether otilonium bromide can influence sensory thresholds of patients suffering from irritable bowel syndrome. METHODS: 15 patients with Rome-II positive IBS were tested by Synectics Visceral Stimulator Barostat using rapid phasic distension (870 ml/min). The sensory threshold for first sensation, stool, pain and maximum tolerable volume and pressure were measured. All of the parameters were tested before and 1 week after the initiation of otilonium bromide (Spasmomen, Berlin Chemie, 3x40 mg) therapy. RESULTS: The perceptual thresholds for first sensation, stool, pain and maximum tolerable distention were, 8.8+/-1.7 Hgmm, 19.2+/-2.1 Hgmm, 26.3+/-2.8 Hgmm, 28.7+/-2.8 Hgmm for pressure, 90+/-21 ml, 145+/-28 ml, 208+/-25 ml, 213+/-28 ml for volume, before treatment, respectively. Otilonium bromide treatment did not influence the thresholds for first sensation and stool, 7.4+/-1.4 Hgmm, 20.7+/-4.6 Hgmm and 83+/-21 ml, 178+/-35.8 ml, respectively. The pressure threshold of pain was significantly higher 1 week after treatment (26.3+/-2.8 Hgmm vs. 29.1+/-5.5 Hgmm, P<0.05), but the volume threshold of this sensation remained unchanged (208+/-25 ml vs. 234+/-39 ml, not significant). The pressure (28.7+/-2.8 Hgmm vs. 38.1+/-3.4 Hgmm, P<0.05) and volume (213+/-28 ml vs. 278+/-27 ml, P<0.05) thresholds for maximum tolerable volume were increased by 7 days otilonium bromide treatment. CONCLUSION: These data suggest that otilonium bromide enhances sensory thresholds to recto-sigmoideal distention.