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Clinical Pharmacokinetics Aug 1995Ondansetron is a potent and highly selective serotonin 5-HT3-receptor antagonist which has demonstrated important antiemetic activity and good tolerability in the... (Review)
Review
Ondansetron is a potent and highly selective serotonin 5-HT3-receptor antagonist which has demonstrated important antiemetic activity and good tolerability in the prevention of chemotherapy-induced nausea and vomiting. Ondansetron is completely and rapidly absorbed from the gastrointestinal tract after oral administration, and does not accumulate with repeated oral administration. Owing to hepatic first-pass metabolism, its bioavailability is only about 60% compared with ondansetron administered by infusion over 15 minutes. Bioavailability is slightly increased when administered after a standard meal, and is not influenced by coadministration of antacids; a slightly enhanced bioavailability has been observed in patients with cancer. Since the time to reach peak concentration is 0.5 to 2 hours after oral ingestion, the drug should be administered at least 30 minutes before chemotherapy. Possible alternative ways of administration of ondansetron include intramuscular, subcutaneous and rectal administration, and oral controlled-release formulations. Ondansetron is widely distributed (volume of distribution approximately 160L) and binds moderately (70 to 76%) to plasma proteins; the elimination half-life averages approximately 3.8 +/- 1 hours. Clearance occurs by hepatic metabolism (95%) rather than renal excretion. Metabolites do not play a role in the activity of the drug, and there is no evidence of genetic polymorphic metabolism. Although aging is associated with decreased clearance and increased bioavailability, dosage adjustments are not required for the elderly, and may be necessary only in patients with severe hepatic impairment. Chemotherapeutic agents do not seem to modify the pharmacokinetics of ondansetron. There remains the question of whether control of emesis is related to systemic availability of ondansetron and, in consequence, the optimal dose and schedule of ondansetron is still to be identified with certainty.
Topics: Animals; Humans; Ondansetron; Serotonin Antagonists
PubMed: 7586904
DOI: 10.2165/00003088-199529020-00004 -
Indian Pediatrics Aug 1995
Review
Topics: Administration, Oral; Adult; Antiemetics; Child; Child, Preschool; Clinical Trials as Topic; Drug-Related Side Effects and Adverse Reactions; Humans; Injections, Intravenous; Nausea; Ondansetron; Radiotherapy; Risk Factors; Vomiting
PubMed: 8635834
DOI: No ID Found -
European Journal of Anaesthesiology.... Nov 1992Ondansetron is a novel 5-HT3 receptor antagonist used for the treatment of cytotoxic-induced emesis and postoperative nausea and vomiting. Safety data from volunteer... (Review)
Review
Ondansetron is a novel 5-HT3 receptor antagonist used for the treatment of cytotoxic-induced emesis and postoperative nausea and vomiting. Safety data from volunteer studies, non-emesis development studies, studies in the treatment of cytotoxic-induced emesis and postoperative nausea and vomiting, and spontaneous case reports, all indicate that ondansetron is well tolerated and has an excellent safety profile. There are no known interactions of ondansetron with other drugs, and no interference with postoperative recovery.
Topics: Drug Tolerance; Humans; Ondansetron; Safety
PubMed: 1425627
DOI: No ID Found -
Paediatric Drugs 2001Ondansetron, a selective serotonin (5-hydroxytryptamine; 5-HT) 5-HT3 receptor antagonist, is an antiemetic agent available for use in adults and children. In children... (Comparative Study)
Comparative Study Review
UNLABELLED
Ondansetron, a selective serotonin (5-hydroxytryptamine; 5-HT) 5-HT3 receptor antagonist, is an antiemetic agent available for use in adults and children. In children receiving ondansetron (multiple 5 mg/m2 or 0.15 mg/kg intravenous and/or oral doses) in addition to chemotherapy in 2 large (n > 100) non-comparative analyses, < or =2 emetic episodes were observed in 33 and 40% of cisplatin recipients, 48 and 68% of ifosfamide recipients, and 70 and 72% of patients receiving other chemotherapeutic regimens. In comparative trials, ondansetron was significantly more effective at reducing nausea and vomiting than metoclopramide or chlorpromazine (both combined with dexamethasone), although the incidence of delayed symptoms were similar between children receiving ondansetron and metoclopramide. In addition, dexamethasone significantly improved the antiemetic efficacy of ondansetron in 1 randomised trial. When used in children undergoing conditioning therapy (including total body irradiation) prior to bone marrow transplantation, ondansetron was significantly better at controlling nausea and vomiting than combined perphenazine and diphenhydramine therapy. In dose-ranging and large placebo-controlled trials, intravenous (0.075 to 0.15 mg/kg) or oral (0.1 mg/kg) ondansetron was significantly more effective than placebo in preventing emesis in children undergoing surgery associated with a high risk of postoperative nausea and vomiting (PONV) including tonsillectomy or strabismus repair. In comparative studies, intravenous administration of ondansetron 0.1 to 0.15 mg/kg was significantly superior to droperidol 0.02 to 0.075 mg/kg or metoclopramide 0.2 to 0.25 mg/kg in preventing emesis in children undergoing various surgical procedures. In comparison with other antiemetics, including prochlorperazine and dimenhydrinate, ondansetron generally showed greater prophylactic antiemetic efficacy. Ondansetron combined with dexamethasone was significantly more effective than ondansetron or dexamethasone alone, as was the combination of ondansetron with a propofol-based anaesthetic compared with either agent alone. Ondansetron is generally well tolerated in children, rarely necessitating treatment withdrawal. The most frequently reported adverse events were mild to moderate headache, constipation and diarrhoea in patients receiving chemotherapy. Wound problems, anxiety, headache, drowsiness and pyrexia were reported most frequently in patients postsurgery.
CONCLUSIONS
Ondansetron has shown good efficacy in the prevention of acute nausea and vomiting in children receiving moderately or highly emetogenic chemotherapy and/or irradiation, particularly when combined with dexamethasone. In the chemotherapy setting, ondansetron is significantly better than metoclopramide and chlorpromazine and has a more favourable tolerability profile. In children undergoing surgery, ondansetron demonstrated superior prophylactic antiemetic efficacy compared with placebo, droperidol and metoclopramide, and was relatively free of adverse events. Ondansetron is thus an effective first-line antiemetic in children undergoing chemotherapy, radiotherapy and surgery.
Topics: Adolescent; Antiemetics; Child; Clinical Trials as Topic; Dexamethasone; Drug-Related Side Effects and Adverse Reactions; Humans; Nausea; Ondansetron; Radiotherapy
PubMed: 11437189
DOI: 10.2165/00128072-200103060-00007 -
European Journal of Anaesthesiology.... Nov 1992Ondansetron is a highly potent and selective antagonist at 5-HT3 receptors. Its anti-emetic actions were first revealed by its ability to antagonize retching and... (Review)
Review
Ondansetron is a highly potent and selective antagonist at 5-HT3 receptors. Its anti-emetic actions were first revealed by its ability to antagonize retching and vomiting induced by chemotherapy and radiotherapy in animals and man. Subsequently, the availability of labelled 5-HT3 receptor ligands allowed identification of 5-HT3 receptors, located at highest densities in the area postrema, nucleus tractus solitarius (NTS), in other areas of the brain, and on afferent terminals of the vagus nerve. Postoperative nausea and vomiting may be caused by various factors: the anaesthetic, associated drugs, the surgical procedure, movement of the patient, sex, weight and pain. These factors mediate their effects via the higher brain circuits, the vestibular nuclei, the chemoreceptor trigger zone in the area postrema, or the upper gastrointestinal tract via the vagus nerve, influencing motor and visceral emetic outputs in the hind-brain. It is hypothesized that ondansetron blocks nausea and vomiting by 5-HT3 receptor antagonism at two specific sites: (i) centrally, in the area postrema/NTS; and (ii) peripherally on vagus nerve terminals. The absence of other pharmacological effects of ondansetron ensures an absence of side-effects.
Topics: Animals; Humans; Nausea; Ondansetron; Postoperative Complications; Vomiting
PubMed: 1425623
DOI: No ID Found -
American Family Physician Apr 2015
Review
Topics: Adolescent; Antiemetics; Child; Diarrhea; Gastroenteritis; Humans; Ondansetron; Vomiting
PubMed: 25884755
DOI: No ID Found -
Alimentary Pharmacology & Therapeutics Jun 2023
Topics: Humans; Ondansetron; Irritable Bowel Syndrome
PubMed: 37161629
DOI: 10.1111/apt.17496 -
Emergency Nurse : the Journal of the... Jun 2021In the UK, the use of antiemetics in children with gastroenteritis is not standardised. The antiemetic ondansetron is often administered, in clinical practice, to... (Review)
Review
In the UK, the use of antiemetics in children with gastroenteritis is not standardised. The antiemetic ondansetron is often administered, in clinical practice, to children presenting with gastroenteritis. However, it is not listed in the British National Formulary for Children for use in gastroenteritis and it is not included in the National Institute for Health and Care Excellence algorithm for the management of gastroenteritis in children under 5 years. This article discusses the findings of a literature review of the outcomes of ondansetron use in children with gastroenteritis in the emergency department. The article concludes that ondansetron appears to be a beneficial and useful adjunct to the treatment of gastroenteritis in children.
Topics: Antiemetics; Child; Emergency Service, Hospital; Gastroenteritis; Humans; Ondansetron
PubMed: 33755371
DOI: 10.7748/en.2021.e2069 -
Alimentary Pharmacology & Therapeutics Jun 2023
Topics: Humans; Ondansetron; Irritable Bowel Syndrome
PubMed: 37161628
DOI: 10.1111/apt.17462 -
Southern Medical Journal May 1993Ondansetron hydrochloride is a new serotonin receptor antagonist that is effective in preventing emesis associated with cancer chemotherapy. The antiemetic effect... (Review)
Review
Ondansetron hydrochloride is a new serotonin receptor antagonist that is effective in preventing emesis associated with cancer chemotherapy. The antiemetic effect appears to be exerted through a peripheral vagal blocking within the gastrointestinal tract, as well as an inhibitory effect within the chemoreceptor trigger zone (CTZ). Plasma concentrations of ondansetron peak 1 hour after an oral dose, and the tablet has an absolute bioavailability of 59%. Ondansetron undergoes extensive hepatic oxidative metabolism in the liver. The half-life of ondansetron is 3.5 hours in healthy volunteers; elderly patients have a slightly reduced clearance, and pediatric patients have increased clearance. Although less than 10% of ondansetron is recovered unchanged in the urine, most metabolites are eliminated by this route. The recommended dose of ondansetron is 0.15 mg/kg for three doses on the day of chemotherapy (30 minutes before chemotherapy and 4 and 8 hours afterward). An alternative regimen includes a single-day dose of 32 mg IV in adult patients before chemotherapy. The efficacy of ondansetron therapy for delayed emesis has not been determined. Ondansetron has proven to be appropriate as a single agent or as an addition to standard antiemetic therapy (ie, corticosteroids, benzodiazepines, neurotransmitter blockers) in preventing and treating acute chemotherapy-induced emesis (CIE). Initial results of clinical trials in prevention of radiotherapy-induced emesis and anesthesia-induced emesis appear positive. Ondansetron is well tolerated, with few adverse events (eg, headache, sedation).
Topics: Antineoplastic Agents; Humans; Ondansetron; Vomiting
PubMed: 8488393
DOI: No ID Found