Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0018681 (headache)
 56,091 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The chemistry, pharmacokinetics, adverse effects, stability, compatibility, and dosage of ondansetron hydrochloride are described, and clinical studies of the use of ondansetron for the prophylaxis of nausea and vomiting induced by antineoplastic therapy are reviewed. Ondansetron hydrochloride is a specific antagonist of serotonin type 3 (5-HT3) receptors, both in the chemoreceptor trigger zone and in the GI tract. Peak plasma concentrations of ondansetron occur approximately one hour after an oral dose and 6 to 20 minutes after an i.v. dose. The mean elimination half-life is approximately 3.5 hours in healthy volunteers, but it is extended in elderly patients (mean of 7.9 hours). In clinical trials, ondansetron has been shown to provide excellent control of nausea and vomiting in patients treated with cisplatin. Comparisons of ondansetron with metoclopramide in patients treated with various types of chemotherapy have shown better response rates with ondansetron. Ondansetron has also been shown to be effective in controlling nausea and vomiting in patients receiving cyclophosphamide with an anthracycline and in patients receiving combination therapy with cyclophosphamide, methotrexate, and fluorouracil. Adverse effects appear to be mild and include headache, constipation, diarrhea and transient abnormalities in liver function tests. The dose of ondansetron (as the hydrochloride salt) for the prophylaxis of chemotherapy-induced nausea and vomiting in adults is 0.15 mg/kg i.v. every four hours for three doses, beginning 30 minutes before antineoplastic therapy. The efficacy of ondansetron is comparable to that of metoclopramide, and the adverse-effect profile is much less problematic. The cost of ondansetron is much higher than that of metoclopramide; thus its use should be limited to patients at high risk for metoclopramide-induced adverse effects and patients in whom metoclopramide is ineffective.
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PMID:Ondansetron--the first of a new class of antiemetic agents. 182 68

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 purpose of this study was to evaluate and compare the antiemetic effectiveness and tolerability of Navoban (tropisetron) and Zofran (ondansetron) following high-dose (> or = 50 mg/m2) cisplatin chemotherapy. In a randomised, multi-centre, double-blind, double-dummy, parallel group study, 117 evaluable chemotherapy-naive patients who received Navoban were compared with 114 who received Zofran. Patient diary cards were used to assess both acute (Day 1) and delayed (Days 2-6) nausea and vomiting. Total control of acute vomiting was achieved in 54% of Navoban and 65% of Zofran patients (p = 0.052), and total control of acute nausea in 66% and 62% respectively (p = 0.655). Total control of delayed vomiting was achieved in 44% of Navoban patients and 46% of Zofran patients (p = 0.765), and of delayed nausea in 56% and 47% respectively (p = 0.207). Both reactions combined were totally prevented during the entire 6-day trial period in 22% of Navoban and 24% of Zofran patients (NS), while a further 42% of patients in both groups remained largely free from both nausea and emesis. The few adverse reactions (e.g. headache, constipation, diarrhoea) were mainly mild and typical of the 5-HT3-receptor antagonists. In conclusion, there were no significant differences in efficacy and tolerability between Navoban 5 mg once daily and the highest recommended dose of Zofran (32 mg on Day 1, followed by 8 mg three times a day).
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PMID:Is Navoban (tropisetron) as effective as Zofran (ondansetron) in cisplatin-induced emesis? The French Navoban Study Group. 774 65

The occurring frequency of 14 most common chemotherapy and anti-nausea drug side-effects was examined. The studies were performed on 29 women with ovarian cancer treated by total number of 125 chemotherapy courses (schedule PAC and Acy) and additionally, in order to eliminate nausea caused by the chemotherapy, by anti-nausea drugs (Zofran, Solu-Medrol, Droperidol, Metoclopramide + Fenactil, Torecan). Zofran caused the fewest number of side-effects, solu-medrol inhibited nausea and vomiting significantly, however it caused many side-effects such as flush on a face, restlessness, incitement and headaches. Torecan did not prevent patients from vomiting. The greatest number of side-effects was observed after droperidol and metoclopramide + fenactil treatment.
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PMID:[Side effects of drug treatment for ovarian cancer after administration of antiemetic drugs]. 814 54

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).
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PMID:Ondansetron: a novel antiemetic agent. 848 93