The effect of paroxetine on the pharmacokinetics, safety, and tolerability of ramosetron in healthy subjects

Comparison of the efficacy of ramosetron and ondansetron in the prophylaxis of postoperative vomiting in children receiving fentanyl by patient-controlled analgesia after orthopedic surgery: a randomized controlled trial

BACKGROUND

This study was designed to compare the efficacy of prophylactic ramosetron and ondansetron in preventing postoperative vomiting in children who received fentanyl by patient-controlled analgesia after orthopedic surgery.

METHODS

Two hundred and eighteen children, 2-15 years old, ASA physical status 1 or 2, scheduled for elective orthopedic surgeries, were randomly divided into the ramosetron group (n = 109) or ondansetron group (n = 109). Patients in ondansetron group received ondansetron 100 μg·kg(-1) and patients in ramosetron group received ramosetron 6 μg·kg(-1) after surgery. Intravenous patient-controlled analgesia with fentanyl was used in both groups. The incidence of postoperative vomiting and side effects were assessed during the 48 h after surgery.

RESULTS

There was significantly less vomiting during the first 24-h and 6-24-h period after surgery in ramosetron group than in ondansetron group (P < 0.01). There were no significant differences in side effect of 5-HT(3) antagonist between the two groups.

CONCLUSION

Ramosetron was more effective during the first 24-h period after surgery than ondansetron in children using fentanyl patient-controlled analgesia after general anesthesia.

Inhibitory effect of ramosetron on corticotropin releasing factor- and soybean oil-induced delays in gastric emptying in rats

BACKGROUND AND AIM

Symptoms of functional dyspepsia (FD) are highly prevalent in patients with irritable bowel syndrome (IBS). However, the effects of therapeutic agents for IBS on the pathophysiology of FD are unclear. In this study, therefore, we examined the effects of ramosetron, a serotonin 5-HT(3) receptor antagonist, on corticotropin releasing factor (CRF)- and soybean oil-induced delays in gastric emptying of rats, in comparison with anti-diarrheal agent and spasmolytics. The involvement of 5-HT and the 5-HT(3) receptor in delayed gastric emptying was also evaluated.

METHODS

Corticotropin releasing factor was administered intravenously to rats 10min before oral administration of 0.05% phenol red solution, and the amount remaining in the stomach was measured after 30min. Soybean oil was administered orally with glass beads, and the number of residual beads in the stomach was counted 1h later.

RESULTS

Both CRF and soybean oil inhibited gastric emptying dose-dependently. Ramosetron and itopride, a gastro-prokinetic agent, significantly reduced both CRF- and soybean oil-induced delays in gastric emptying, while an anti-diarrheal agent and spasmolytics aggravated them. Pretreatment with p-chlorophenylalanine for 2days to reduced the synthesis of endogenous 5-HT diminished the effects of both CRF and soybean oil on gastric emptying. A 5-HT(3) receptor agonist m-chlorophenylbiguanide suppressed gastric emptying of both phenol red and glass beads, and those effects were reversed by ramosetron.

CONCLUSIONS

These results suggest that CRF and soybean oil suppress gastric emptying in rats by activating 5-HT(3) receptors, and that by antagonizing these receptors, ramosetron may ameliorate symptoms of FD in clinical settings.