Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0042963 (vomiting)
 31,883 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Ondansetron represents a new class of drugs that exert their antiemetic activity by selective inhibition of a serotonin receptor subtype (5-HT3). Ondansetron has marked activity against emesis associated with cisplatin and other highly emetogenic drugs. Compared with high doses of metoclopramide, the antiemetic "gold standard," it demonstrates equal or superior efficacy. Although ondansetron is moderately well absorbed after oral administration, only a parenteral formulation will initially be available. Ondansetron is eliminated almost entirely by hepatic metabolism; less than five percent of an intravenously administered dose is recovered intact in urine. The half-life of ondansetron is approximately 3.5 hours; slightly shorter in children and prolonged in the elderly. Neither clinical efficacy nor adverse effects have correlated with serum concentrations. Ondansetron is generally well tolerated. Clinically relevant adverse effects include headache, diarrhea or constipation, sedation, and transient minor elevations of liver function tests. It is not associated with extrapyramidal reactions. Ondansetron is indicated as prophylaxis for nausea and vomiting associated with emetogenic chemotherapy. Studies to further evaluate and define its use are ongoing.
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PMID:Ondansetron: a serotonin receptor (5-HT3) antagonist for antineoplastic chemotherapy-induced nausea and vomiting. 183 88

The efficacy and safety of two dose schedules of the 5-HT3 antagonist ondansetron (Zofran) were studied in 35 patients (group A: 19 patients, group B: 16 patients) previously refractory to standard antiemetics after non-cisplatin-based chemotherapy (greater than 5 emetic episodes). The maintenance of the antiemetic efficacy of ondansetron was further studied in 28 patients (13 A, 15 B) in respectively 36 and 48 retreatment courses. Ondansetron was administered as an 8 mg loading dose (A: 4 mg i.v. + 4 mg orally; B: 8 mg i.v.), followed by oral treatment for 5 days (A: 6-hourly; B: 8 mg 8-hourly). In the first treatment cycle acute emesis was completely controlled in 53% of the patients in group A and in 50% of the patients in group B. Delayed emesis was absent in 75% and 38% of the patients in group A and B respectively. In a second treatment cycle acute antiemetic control was achieved in 54% and 53% of the patients in group A and B respectively. Over the third and fourth subsequent treatments, complete control occurred in 56% and 38% of the patients in group A, and in 46% and 56% of the patients in group B respectively. Delayed emesis did not occur over the following courses in 62%, 89% and 75% of the patients on regimen A, in 57%, 60% and 63% of the patients on regimen B. The observed adverse effects were headache (37%) and constipation (42%). No extrapyramidal reactions were seen. Ondansetron is able to re-establish an acceptable antiemetic control in previously refractory patients on non-cisplatin-based chemotherapy, without major toxicity. This efficacy is maintained over the three following retreatment courses.
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PMID:The 5-HT3 receptor antagonist ondansetron re-establishes control in refractory emesis induced by non-cisplatin chemotherapy. 183 61

The antiemetic activity of DAU 6215, a novel antagonist of 5-HT3 receptors, was investigated in animal models of cytotoxic treatment-evoked emesis and compared with the antiemetic activity of ondansetron and metoclopramide. In dogs, vomiting was induced by i.v. cisplatin; in ferrets, the emetic response was elicited by i.v. doxorubicin or X-ray exposure. Pretreatment with 0.1-1 mg/kg DAU 6215 given i.v. or p.o. prevented the vomiting response to the different emetic agents. In the dog, the antiemetic potency of metoclopramide was 30 times lower than that of DAU 6215. Ondansetron was less potent than DAU 6215 against cisplatin and doxorubicin but was equally effective in the radiotherapy protocol. In this model, lengthening of the pretreatment time to 2 h did not affect the antiemetic efficacy of DAU 6215, whereas it decreased that of ondansetron. The results demonstrate that DAU 6215 is a highly effective and long-lasting inhibitor of cytotoxic treatment-induced emesis in different animal species.
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PMID:Antiemetic activity of the new 5-HT3 antagonist DAU 6215 in animal models of cancer chemotherapy and radiation. 183 59

Serotonin (5-Hydroxytryptamine) seems to play a dominant role in triggering vomiting induced by cytotoxic agents through the stimulation of 5-HT3 receptors. They have been observed in the GI tract as well as in the brain (area postrema). Ondansetron is a specific antagonist of 5-HT3 serotonin receptors. Its anti-emetic activity is very powerful in the ferret. The availability of an injectable or oral form of this product allows the overall treatment of acute and delayed emesis and its administration is in accordance with different schedules: single IV injection or a continuous 24 hour infusion or repeated IV injection followed by oral treatment. The pharmacokinetics of the drug are as follows: absorption begins about 30 minutes after the administration per os, its biodisponibility is about 60%, its clearance: 20 ml/minute and its elimination half life about 3 hours. Different double blind studies, carried out in parallel groups or in cross over, demonstrated the superiority of ondansetron over metoclopramide in the control of nausea and vomiting, whether or not the chemotherapy contained cisplatin; a more recent study shows also that ondansetron was superior to alizapride and methylprednisolone in combination. Side effects of ondansetron do not include extrapyramidal symptoms but only headaches and constipation. The use of ondansetron improves the well-being of patients receiving chemotherapy and increases protocol compliance.
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PMID:[Ondansetron: a specific 5-HT3 serotonin receptor inhibitor, a new antiemetic in oncology]. 183 90

Despite a number of significant advances over the past decade, prevention and treatment of chemotherapy-induced emesis remain formidable problems, particularly with cisplatin-containing regimens. Nearly one third of patients receiving high-dose cisplatin still experience substantial emesis despite the best available conventional antiemetics, and the toxic effects of these agents remain quite troublesome. In recent years, a new class of agents, the serotonin antagonists, has been identified. These agents hold promise for clinical utility in a wide range of areas. Selective antagonists of the serotonin (5-hydroxytryptamine) type 3 (5-HT3) receptor have proven in early clinical trials to be potent antiemetic agents in patients receiving cytotoxic chemotherapy, with efficacy comparable to or superior to that of conventional antiemetics. Toxic effects to date with the 5-HT3 receptor antagonists have been modest. The current state of knowledge with respect to these agents as antiemetics for patients receiving cytotoxic chemotherapy is summarized.
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PMID:Serotonin antagonists: a new class of antiemetic agents. 185 Aug 6

Chemotherapy-induced emesis is the most severe side effect in term of patient's perception. Current anti-emetic regimen as high dose metoclopramide can achieve a complete response in less than 60% of patients. The HT3 receptors appear to be the principal mediator of the emetic effect and their blockade have a clear activity in the prevention of acute drug-induced emesis, superior to reference regimens.
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PMID:5HT3-antagonist receptors: their role in drug-induced emesis. 198 28

Antiemetic effects of serotonin 5-HT3 receptor antagonists (ICS205-930, zacopride, BRL43694, GR38032F) were investigated in Suncus murinus. Veratrine, nicotine, copper sulfate, cisplatin, cyclophosphamide and motion sickness were used as emetic stimuli. Serotonin 5-HT3 receptor antagonists did not inhibit emetic responses to veratrine, nicotine, copper sulfate and motion sickness. However, cisplatin- and cyclophosphamide-induced emesis was strongly blocked by them. Both subcutaneous and intravenous injections of 5-HT3 antagonists were effective. Serotonin 5-HT1 and 5-HT2 receptor antagonists were less effective. These results clearly indicate that a 5-HT3 receptor-mediated mechanism(s) is involved in the emesis caused by cancer chemotherapeutic agents and that 5-HT3 receptor antagonists are very effective as prophylactic drugs.
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PMID:Selective blockade of cytotoxic drug-induced emesis by 5-HT3 receptor antagonists in Suncus murinus. 204 Dec 20

In ferrets, the oral emetic activity of zacopride was compared with its R- and S-enantiomers. Increasing doses of 0.01, 0.1, 1.0, 10.0 and 31.6 mg/kg of zacopride or its 2 enantiomers were each administered at hourly intervals to separate groups of animals until emesis occurred. The emetic (100%) dose for zacopride and its S-enantiomer was 0.11 mg/kg p.o. (cumulative dose). The R-enantiomer at a cumulative dose of 42.71 mg/kg p.o. produced emesis in 25% of the animals. By the i.p. route zacopride and its S-enantiomer were more potent than the R-enantiomer in blocking the emetic activity of 0.1 mg/kg p.o. of zacopride. The involvement of 5-HT3 mechanisms is indicated by a correlation between zacopride and its enantiomers to cause and prevent emesis and their affinity at 5-HT3 binding sites. Further, the putative 5-HT3 agonists, 2-methyserotonin and phenylbiguanide, at 10 mg/kg p.o., produced emesis that was blocked by zacopride (0.1 mg/kg i.p.) or ICS 205-930 (1 mg/kg i.p.). The results suggest that in the ferret the S-enantiomer is predominantly responsible for both the emetic and antiemetic properties of zacopride and that 5-HT3 agonism and antagonism are involved in these actions.
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PMID:Studies on the emetic and antiemetic properties of zacopride and its enantiomers. 205 36

Drugs that enhance gastrointestinal motility include the benzamide drugs metoclopramide, cisapride and renzapride (BRL-24924). Because these agents also are serotonin-3 (5-HT3) receptor antagonists, which can promote gastric emptying in some species, the motor-stimulating properties of benzamide agents may be due to this mechanism. Metoclopramide (0.3-3.0 mg/kg i.v.), cisapride (0.03-1.0 mg/kg i.v.) and BRL-24924 (0.01-0.1 mg/kg i.v.) were evaluated for their relative motility-stimulating and 5-HT3 receptor antagonist activities in conscious dogs and were compared with selective 5-HT3 antagonist antiemetic compounds ICS-205-930, (3 alpha-tropanyl)1-H-indole-3-carboxylic acid ester and granisetron (BRL-43694). Gastric antral contractions and intestinal myoelectric motility were determined in response to drugs, as were their effects on solid and liquid emptying in a gamma scintigraphic model of gastroparesis. 5-HT3 receptor antagonist potency was examined by deriving ED50 values for inhibition of cisplatin emesis. All drugs were 5-HT3 antagonists as they blocked cisplatin emesis with relative potencies of BRL-43694 = ICS-205-930 greater than BRL-24924 greater than cisapride = metoclopramide. The order of potency for stimulating fasted dog antral contractile activity, however, was BRL-24924 = cisapride greater than metoclopramide greater than ICS-205-930 = BRL-43694. Maximally effective doses of BRL-24924 (0.1 mg/kg i.v.) and cisapride (0.67 mg/kg i.v.) in the antrum also stimulated intestinal myoelectrical activity, whereas ICS-205-930 (0.5 and 2.0 mg/kg i.v.) was not active.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Relationship of serotonin-3 receptor antagonist activity to gastric emptying and motor-stimulating actions of prokinetic drugs in dogs. 207 88

Thirty children aged 2-16 years with malignant tumours who were receiving chemotherapy were treated with the 5-HT3 antagonist ondansetron. Each received a single intravenous dose (5 mg/m2) followed by oral doses (2-4 mg depending on surface area) every eight hours for five days. Chemotherapy regimens comprised: carboplatin alone, carboplatin plus etoposide, cisplatin plus etoposide; adriamycin (doxorubicin) plus cyclophosphamide, or ifosfamide. Twelve patients received ondansetron with their first course of chemotherapy and the other patients were poor responders to previous antiemetic treatment. Efficacy was assessed by a questionnaire documenting the incidence of vomiting and severity of nausea. In a 24 hour period after starting chemotherapy a complete or major response (less than two vomiting episodes) was achieved in 87% of children. Although ondansetron was effective for early antiemesis after cisplatin or ifosfamide, delayed vomiting, retching, or nausea reduced responses to 50% and 20%, respectively. We conclude that in children ondansetron is an effective, well tolerated, oral antiemetic enabling simple administration in the outpatient setting. In the present schedule it was of limited efficacy against cisplatin or ifosfamide induced emesis.
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PMID:5-HT3 antagonist ondansetron--an effective outpatient antiemetic in cancer treatment. 214 21


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