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PubMed2004

Systematic review of the efficacy of antiemetics in the treatment of nausea in patients with far-advanced cancer.

OBJECTIVES: To systematically review studies of antiemetics used in the treatment of nausea in patients with far-advanced cancer. DATA SOURCES: Randomized controlled trials (RCT) and uncontrolled studies identified by electronic and hand searching. REVIEW METHODS: Identified studies were appraised for quality and effect size. RESULTS: Of 21 studies included, 2 were systematic reviews, 7 were RCT and 12 were uncontrolled studies or case series. Differences in interventions and outcomes amongst the RCT precluded any quantitative data synthesis and all seven studies were prone to bias. Whereas uncontrolled studies indicated a high response rate to standard regimens (75-93% for both nausea and vomiting), RCT showed much lower response rates to these agents (23-36% for nausea, 18-52% for vomiting). The two methods of antiemetic choice (choice based either on the inferred mechanism or empirical) were equally effective. There is reasonably strong evidence for the use of metoclopramide in cancer-associated dyspepsia and steroids in malignant bowel obstruction. There was conflicting evidence about the efficacy of serotonin antagonists compared with standard treatments (e.g. metoclopramide, dopamine antagonists and dexamethasone). There was little or no evidence of the efficacy of some commonly used and seemingly effective drugs such as haloperidol, cyclizine, and methotrimeprazine. CONCLUSION: Evidence supporting the existing consensus-based guidelines for management of nausea and vomiting in advanced cancer is sparse. Current approaches to treatment based on the neuropharmacology of the emetic pathway may be inappropriate in this setting. Well-designed studies of the impact of "standard" management and novel agents on nausea and vomiting in palliative populations are needed.

Antiemetics↗
PubMed2004

Radiotherapy-induced nausea and vomiting (RINV): antiemetic guidelines.

As many as 40-80% of patients undergoing radiotherapy (RT) will experience nausea and/or vomiting, depending on the site of irradiation. Fractionated RT may involve up to 40 fractions over a 6-8 weeks period, and prolonged symptoms of nausea and vomiting could affect quality of life. Furthermore, uncontrolled nausea and vomiting may result in patients delaying or refusing further radiotherapy. Nausea and vomiting are often underestimated by radiation oncologists. Incidence and severity of nausea and vomiting depend on RT-related factors (single and total dose, fractionation, irradiated volume, radiotherapy techniques) and patient-related factors (gender, general health of the patient, age, concurrent or recent chemotherapy, psychological state, tumor stage). Current antiemetic guidelines prescribe the emetogenicity of radiotherapy regimens and recommend the use of 5-HT(3) antagonists with or without a steroid for prophylaxis in moderately and highly emetogenic treatment (MASCC, ASCO, ASHP, NCCN). The new proposed guidelines summarise the updated data from the literature and take into consideration the existing guidelines. According to the irradiated area (the most frequently studied risk factor), the proposed guidelines are divided into four levels of emetogenic risk: high, moderate, low and minimal. They offer guidance to prescribing physicians for effective antiemetic therapies in RINV.

Antiemetics↗
PubMed2006

Acupuncture and acupressure for the prevention of chemotherapy-induced nausea--a randomised cross-over pilot study.

OBJECTIVE: To investigate whether a combination of acupuncture and acupressure is effective for reducing chemotherapy-induced nausea and vomiting. PATIENTS AND METHODS: In a randomised cross-over trial, 28 patients receiving moderately or highly emetogenic chemotherapy and conventional standard antiemesis were treated for one chemotherapy cycle with a combination of acupuncture and acupressure at point P6 and for one cycle at a close sham point. The main outcome measure was a nausea score derived from daily intensity rating. RESULTS: There was no difference between combined acupuncture and acupressure treatment at P6 and at the sham point for the nausea score, but the level of nausea was very low in both phases. The mean nausea score was 6.2 (standard deviation 9.0) for treatment at P6 and 6.3 (9.1) for treatment at the sham point (mean difference -0.1, 95% confidence interval -3.9 to 3.7; p=0.96). Seventeen of 21 participants completing the study would desire acupuncture and acupressure for future chemotherapy cycles, but there was no clear preference for either point. CONCLUSION: In this small pilot study a significant difference between treatment at P6 and a close sham point could not be detected. However, it cannot be ruled out that an existing difference was missed due to the small sample size.

Acupressure↗
PubMed2001

Nausea and emesis: evidence for a biobehavioral perspective.

Abstract. For most people, nausea and vomiting (NV) are simply unfortunate consequences of overindulgent college days or overenthusiastic amusement rides. Yet for most cancer patients, nausea and vomiting (also referred to as emesis) remain among the most frequent side effects of cancer chemotherapy. Patients typically view control of nausea as more important than control of emesis, while physicians and nurses judge emesis control to be more important to antiemetic efficacy than nausea control. The 5-HT3 receptor antagonists have been shown to be clinically more effective in controlling emesis, particularly that caused by regimens containing high-dose cisplatin, than previously available agents. Disappointingly, however, these drugs do not appear to be more effective than previous antiemetics in reducing nausea. In addition, the 5-HT3 receptor antagonists may become less effective over repeated chemotherapy administrations, and they remain expensive. An impediment to research progress has been an insularity that has prompted two parallel research efforts: one searching for biological understanding to enhance pharmacological intervention(s) and the other searching for psychological understanding to aid in developing more effective behavioral intervention(s). While both approaches have been successful, it is time to have the two views merge into a biobehavioral framework that combines them both. This paper draws on both physiological and psychological origins of NV to begin the development of a biobehavioral model of development that integrates features of both approaches.

Antiemetics↗
PubMed2005

Sickness and satiety: physiological mechanisms underlying perceptions of nausea and stomach fullness.

The pathophysiology of nausea and the physiological mechanisms underlying perceptions of stomach emptiness and fullness are not clearly understood, but several potentially important factors have been identified. Gastric dysrhythmias are believed to contribute to the subjective experience of nausea and may also be involved with perceptions of stomach emptiness, hunger, and even dyspepsia symptoms like bloating and early satiety. Normal gastric neuromuscular function is more evident in the absence of nausea and is also thought to be related to feelings of satiety or comfortable stomach fullness. Autonomic and endocrine influences may also play a critical role in the pathophysiology of nausea and abnormal perceptions of stomach emptiness or fullness. Achieving a better understanding of the gastric neuromuscular and neurohormonal influences on perceptions arising from the viscera may prove invaluable in the development of novel treatments for such conditions as unexplained nausea, functional dyspepsia, and obesity.

Autonomic Nervous System↗
PubMed1994

The prevention of radiosurgery-induced nausea and vomiting by ondansetron: evidence of a direct effect on the central nervous system chemoreceptor trigger zone.

Nausea and emesis are significant side effects in patients undergoing stereotactic radiosurgery for brain lesions in the region of the chemoreceptor trigger zone (area postrema of the brain). Even with the current antiemetic treatment (prochlorperazine +/- corticosteroids), those side effects remain significant. The purpose of this study is twofold: [1] to evaluate the efficacy of ondansetron in inhibiting nausea and emesis in stereotactic radiosurgery patients and [2] to demonstrate that ondansetron's locus of action is the central nervous system (CNS) chemoreceptor trigger zone in the area postrema. In a pilot study, 10 patients receiving > or = 350 cGy in a single fraction of radiosurgery to the region of the area postrema received 32 mg ondansetron iv 1 hour prior to treatment +/- corticosteroids. In a retrospective analysis these results were compared to those of patients with similar features (and matched for radiation dose to the area postrema and the dose of corticosteroids) who received prochlorperazine +/- corticosteroids. Nine of 10 patients in the ondansetron group had no nausea or emesis within 48 hours after treatment; one patient experienced one episode of emesis. In the prochloreperazine group, eight patients had symptoms, three patients needed hospitalization or a physician's care for emesis within 24 hours, and five had nausea with no specific treatment. These preliminary results suggest that ondansetron is a safe and efficient drug to prevent nausea and emesis in this patient group. The precise mechanism of action of ondansetron in these patients is unknown, but is likely due to the drug's serotonin-blocking effect within the CNS. A randomized, prospective study has been started at our institution to confirm these preliminary results.

Adult↗
PubMedDate not supplied

Intravenous droperidol decreases nausea and vomiting after alfentanil anesthesia without increasing recovery time.

The frequency rate of nausea and vomiting after an alfentanil-based anesthetic is high, with reported frequencies of 38% to 68%. This study was undertaken to evaluate the efficacy of low-dose and moderate-dose droperidol in decreasing the frequency of postoperative nausea and vomiting and to evaluate whether droperidol has any effect on slowing recovery after a standard alfentanil-based anesthetic. Sixty normal adults who were scheduled to undergo short surgical procedures requiring general anesthesia were assigned randomly in a double-blind manner to one of three groups of 20: (1) control--normal saline; (2) droperidol 10 micrograms/kg; or (3) droperidol 20 micrograms/kg. A standard alfentanil-based anesthetic was used, and the study drug was given immediately after induction of anesthesia. In the post-anesthesia recovery room, all patients were evaluated according to the Aldrete score, noting the time to achieve a score of 10. Presence or absence and severity of nausea and vomiting were noted. To assess psychomotor recovery, a Trieger dot test was performed by every patient preoperatively, at the time of an Aldrete score of 10, and upon discharge from the recovery room. There was no statistical difference between the groups in age, sex, type of procedure, weight, total dose of alfentanil, or duration of anesthetic. The frequency of nausea and vomiting was significantly less (p less than 0.05) for the 20 micrograms/kg group (5%) than for the 10 micrograms/kg group (25%) or the control group (40%). A dose-response relationship was evident for the antiemetic effect of droperidol. An analog scale for severity of nausea and vomiting also demonstrated a dose response effect.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMedDate not supplied

A double-blind, placebo-controlled pilot study examining the effectiveness of intravenous ondansetron in the prevention of postoperative nausea and emesis.

STUDY OBJECTIVE: To compare the efficacy and safety profiles of ondansetron and a placebo when infused immediately prior to anesthesia induction for the prevention of postoperative nausea and emesis (vomiting or retching). DESIGN: Randomized, double-blind, placebo-controlled, parallel, multicenter pilot study. SETTING: Three U.S. ambulatory surgical facilities. PATIENTS: One hundred eighty ASA physical status I and II women scheduled to undergo ambulatory gynecologic surgical procedures while receiving general endotracheal anesthesia. INTERVENTIONS: Ondansetron 8 mg or a placebo (equivalent volume) was given intravenously (IV) prior to anesthesia induction to prevent postoperative nausea and vomiting. MEASUREMENTS AND MAIN RESULTS: For the first 24 hours following emergency from anesthesia, patients were monitored in the postanesthesia care unit by a research observer and at home via telephone contact and diary cards. More patients in the ondansetron group (62%) than in the placebo group (40%) were emesis-free over the 24-hour study period (p = 0.005). Ondansetron also was more efficacious than the placebo over the 24-hour study period when a surgery duration of more than 45 minutes was considered in the analyses. For all patients, regardless of surgery duration, there was a low degree of nausea during the course of the study. In all instances, the degree of nausea was slightly lower for ondansetron-treated patients than for placebo-treated patients; however, in no instances were the differences statistically significant. Ondansetron and placebo had similar safety profiles as established by laboratory test results, vital sign monitoring, and adverse event reporting. CONCLUSION: Ondansetron, infused IV before anesthesia induction, appears to be safe and effective when used in the prevention of postoperative nausea and emesis.

Adult↗
PubMedDate not supplied

A randomized, double-blind pilot study examining the use of intravenous ondansetron in the prevention of postoperative nausea and vomiting in female inpatients.

STUDY OBJECTIVE: To compare the efficacy and safety profiles of intravenous (IV) ondansetron (two 8 mg doses 8 hours apart) and a placebo when used in the prevention of postoperative nausea and emesis (vomiting or retching). DESIGN: Randomized, double-blind, placebo-controlled, parallel, multicenter pilot study. SETTING: Four university hospitals in the United States. PATIENTS: Two hundred seven women scheduled to undergo inpatient surgical procedures during general anesthesia. INTERVENTIONS: Patients were randomized to receive, in a double-blind fashion, either two 8 mg doses of IV ondansetron or a placebo. The first study drug dose was administered before induction of anesthesia; the second dose was given 8 hours later. Each study drug dose was admixed with normal saline to 20 ml and administered IV over 2 to 5 minutes. Vital signs were monitored immediately before and 1 minute after completion of the study drug infusion. MEASUREMENTS AND MAIN RESULTS: For the 24-hour period following operation, 60% of the patients who received ondansetron and 26% of the patients who received the placebo were emesis-free (p < 0.001). Subanalyses based on patients' previous history of general anesthesia indicated that ondansetron was superior to the placebo in preventing emesis regardless of history [66% vs. 33% in patients who had never had general anesthesia or had had no nausea or emesis following previous anesthesia (p = 0.001) and 50% vs. 17% in patients who had nausea or emesis following previous anesthesia (p = 0.005)]. Ondansetron also was superior to the placebo for the prevention of nausea over the 24-hour study period regardless of anesthesia history. Ondansetron was generally well tolerated. The adverse event, vital sign, and clinical laboratory test profiles were similar to those for the placebo. No patient who received ondansetron had untoward changes in central nervous system function, including sedation. CONCLUSIONS: Prophylactic IV ondansetron appears to be safe and causes a significant reduction in the frequency and severity of postoperative nausea and emesis.

Adolescent↗
PubMed1996

Incidence of nausea and vomiting in outpatients undergoing general anesthesia in relation to selection of intraoperative opioid.

STUDY OBJECTIVE: To measure the incidence of nausea and vomiting in outpatients in relation to selection of, or withholding of, intraoperative opioid. DESIGN: Prospective, randomized, double-blind control trial. SETTING: University general hospital. PATIENTS: 200 unpremedicated ASA status 1 and 11 patients, 8 to 80 years old, undergoing general anesthesia for ambulatory surgery. INTERVENTION: Patients were randomized to four groups, three of which received equipotent doses of different opioids intravenously (i.v.) during induction of anesthesia. Group 1 received nalbuphine 0.25 mg/kg, Group 2, alfentanil 20 ug/kg; Group 3, fentanyl 2 ug/kg; and Group 4, normal saline. MEASUREMENTS AND MAIN RESULTS: We evaluated (1) incidence and severity of nausea and vomiting in the postanesthesia care unit (PACU) and over the next 24 hours; (2) time to PACU discharge; (3) need for antiemetic therapy; and (4) need for analgesic rescue in the PACU. The incidences of nausea and vomiting were similar in all groups, as were time to discharge, antiemetic, and nonsteroidal antiinflammatory drug requirements. The highest incidences of nausea and vomiting occurred at 6 hours in all groups (23% and 9.5%, respectively). Group 1 required lower rescue doses of morphine in the PACU but this result may have been an artifact due to employing the mixed agonist-antagonist opioid, nalbuphine, in this group. CONCLUSIONS: Opioid administration at the doses employed during induction of anesthesia does not promote postoperative nausea or vomiting, nor increase length of stay in the PACU.

Adolescent↗
PubMed2006

Treatment of nausea and vomiting: gaps in our knowledge.

The past 20 years have seen notable advances in our understanding of the physiology and pharmacology of the emetic reflex leading to the identification of the anti-emetic effects of 5-hydroxytryptamine(3) (5-HT(3)) and neurokinin(1) receptor (NK(1)) antagonists. The introduction of 5-HT(3) and NK(1) receptor antagonists into the clinic has had a major impact in alleviating the nausea and vomiting associated with the treatment of cancer and the sequelae to anaesthesia and surgery (post-operative nausea and vomiting, PONV). Despite these advances there are major gaps in our understanding. Interestingly, one of these is the relatively poor ability to treat nausea. Additional gaps in our knowledge are highlighted to provide a framework within which directions for research can be proposed. Particular attention is drawn to: lacunae in knowledge of some currently used anti-emetics such as the source of dopamine required to initiate emesis; the theoretical assumptions and mechanisms underlying the concept of a "universal anti-emetic"; the variety of receptors at which agonists act to have anti-emetic effects (GABA (B), CB(1), 5-HT(1A), ghrelin, opioid); issues of translation from animals to humans and the relationship between the pathways involved in emesis and certain gastrointestinal disorders such as dyspepsia and gastroesophageal reflux, with the latter being of particular interest as some agents affecting reflux are also anti-emetic. Together, the unmet clinical need to adequately control nausea, possibly by new drugs acting within the brainstem, and the significant gaps in understanding key aspects of the emetic reflex, suggest an important need to focus and re-direct research into the distressing and sometimes life-threatening symptoms of nausea and vomiting.

Animals↗
PubMed2005

The oral NK(1) antagonist aprepitant for the prevention of acute and delayed chemotherapy-induced nausea and vomiting: Pooled data from 2 randomised, double-blind, placebo controlled trials.

In this work, data from two phase III studies were pooled to further evaluate the NK(1) antagonist aprepitant for prevention of cisplatin induced nausea and vomiting. One thousand and forty three patients receiving cisplatin (> or = 70 mg/m2) were randomised to receive either a control regimen (32 mg intravenous ondansetron [O] and 20 mg oral dexamethasone [D] on day 1; 8 mg D twice daily on days 2-4) or an aprepitant (A) regimen (125 mg A plus 32 mg O and 12 mg D on day 1, 80 mg A and 8 mg D once daily on days 2-3, and 8 mg D on day 4). The primary endpoint was no emesis and no rescue therapy. Potential correlations between acute and delayed emesis were assessed, as were frequency of emetic episodes by time interval and effects on nausea and quality of life as measured by the functional living index emesis (FLIE) questionnaire. In the aprepitant group, there was statistically significantly less nausea over the study period as well as higher functioning on the FLIE questionnaire in both the nausea and vomiting domains. Patients without acute emesis were more likely to have no emesis in the delayed phase. Compared with control, the aprepitant regimen improved prevention of delayed emesis by 16% points in patients without acute emesis, and by 17% points in patients with acute emesis. Among patients who did not have complete response, the frequency of emesis at various intervals over 5 days was consistently lower in patients receiving aprepitant. Analyses of this combined Phase III population further characterized the clinical profile of the aprepitant regimen, showing that delayed emesis is correlated with, but not entirely dependent on, the presence of acute emesis, and that aprepitant has a favorable effect against nausea throughout 5 days postchemotherapy. In addition, even among patients who had emesis or needed rescue therapy, aprepitant was associated with a lower frequency of these events compared with the control regimen.

Acute Disease↗
PubMed2004

Morphine induces less nausea than meperidine when administered parenterally.

The objective of our study is to identify and compare the prevalence of nausea after parenteral administration of opioids in the Emergency Department (ED). This prospective study utilized a convenience sample at a community-based ED with a volume of 60,000 annual visits. Patients who were in acute pain or had an exacerbation of chronic pain requiring treatment with an opioid analgesic agent were eligible. Demographic and historical features were recorded on a standardized closed data collection form. The main study endpoint was the occurrence of nausea. The prevalence of nausea and vomiting was compared between morphine and meperidine. There were 37 patients in the morphine group and 156 in the meperidine group. The two groups were similar with respect to mean age, gender, and weight. The reported nausea was 0 of 37 in the morphine group and 20 of 156 (12.8%) in the meperidine group. This difference between morphine and meperidine groups of 12.8% (95% confidence intervals 2-24%) was statistically significant. In our patient population, morphine caused significantly less nausea then meperidine when it was used as an analgesic in the ED.

Adult↗
PubMedDate not supplied

A comparison of different severities of nausea and vomiting during pregnancy relative to stress, social support, and maternal adaptation.

A cross-sectional and comparative research design with convenience sampling was used to recruit pregnant women from prenatal clinics in southern Taiwan between 2002 and 2003 to examine the differences in perceived stress, social support, and maternal psychosocial adaptation among women with different severities (mild or less than mild, moderate, and severe) of nausea and vomiting during pregnancy. A total of 150 pregnant women participated in this study. One-way analysis of variance indicated that perceived stress was significantly different among the 3 groups. The least significant difference post-hoc test revealed that pregnant women with mild nausea and vomiting had significantly lower stress than did pregnant women with severe nausea and vomiting. The severity of nausea and vomiting was significantly associated with the Prenatal Self Evaluation Questionnaire subscales for "acceptance of pregnancy" and "fear of helplessness and loss of control in labor." Social support and maternal psychosocial adaptation were not significantly different among these three groups. The degree of perceived stress and maternal psychosocial adaptation may be related to the severity of nausea and vomiting during pregnancy.

Adult↗
PubMed2000

Granisetron, droperidol, and metoclopramide for the treatment of established postoperative nausea and vomiting in women undergoing gynecologic surgery.

OBJECTIVE: The aim of this study was to evaluate granisetron, droperidol, and metoclopramide for efficacy and safety in the treatment of established postoperative nausea and vomiting after major gynecologic surgery. STUDY DESIGN: One hundred twenty postoperative female patients were monitored for the first 3 hours after anesthesia in the postanesthesia care unit and for the next 24 hours after anesthesia in the ward. Patients who had postoperative nausea and vomiting within the first 3 hours after anesthesia received intravenously, in a randomized double-blind manner, 40 microg/kg granisetron, 20 microg/kg droperidol, or 0.2 mg/kg metoclopramide. Patients were then observed for 24 hours after drug administration. RESULTS: Complete control of established postoperative nausea and vomiting, defined as no emesis and no need for another rescue antiemetic medication, was more frequent among the patients who had received granisetron (88%) than among those who had received droperidol (55%) or metoclopramide (50%) (P <.05). The severity of nausea was less in patients who had received granisetron than in those who had received droperidol or metoclopramide (P <.05). No clinically adverse events were observed in any of the groups. CONCLUSION: Granisetron is more effective than droperidol or metoclopramide for the treatment of established postoperative nausea and vomiting during the first 3 hours after anesthesia in patients undergoing major gynecologic operations.

Adult↗
PubMed1997

The development of anticipatory nausea in patients receiving adjuvant chemotherapy for breast cancer.

Previous research on anticipatory nausea in cancer patients has focused on its occurrence in the clinic before chemotherapy infusions. The present study is the first, to our knowledge, to examine the development of anticipatory nausea across eight chemotherapy infusions for three time periods (night before, morning of, and immediately prior to each infusion). Based on classical conditioning experiments conducted with animal subjects, we hypothesized that the severity of anticipatory nausea would increase as the time for scheduled infusions approached. Eighty-two women diagnosed with Stage I or II breast cancer were assessed for the intensity of anticipatory nausea at three time periods prior to eight scheduled infusions of outpatient adjuvant chemotherapy. Analyses indicated a significant interaction between number of infusions experienced and temporal proximity to the infusion, supporting the hypothesis. Changes in the severity of anticipatory nausea across infusions were consistent with conditioned learning predictions. These results contribute to a growing recognition of the importance of conditioning principles for understanding side effects of chemotherapy for cancer and may have implications for the management of side effects secondary to a variety of pharmacotherapies in clinical practice.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed2003

Effect of gabapentin on nausea induced by chemotherapy in patients with breast cancer.

In an anecdotal report, complete resolution of chemotherapy-induced nausea was seen in a patient with breast cancer, after she was placed on the anticonvulsant gabapentin. On this basis, we did an open-label study in which oral gabapentin 300 mg thrice daily was given for every other chemotherapy treatment in nine patients with breast cancer. Six of the nine reported at least a three-point improvement in peak delayed nausea (on an eight-point nausea scale), and three patients had complete resolution of nausea when taking gabapentin. This preliminary evidence shows that gabapentin might have a role in treatment of chemotherapy-induced nausea.

Acetates↗
PubMed1999

Intravenous ondansetron for the control of opioid-induced nausea and vomiting. International S3AA3013 Study Group.

This randomized, double-masked, placebo-controlled, multicenter trial was conducted in 9 countries to assess the safety and efficacy of 2 doses of intravenous ondansetron (8 and 16 mg) for the control of opioid-induced nausea and vomiting. A total of 2574 nonsurgical patients who presented with pain requiring treatment with an opioid analgesic agent participated in this trial. The most common presenting painful condition was back or neck pain, reported by approximately one third of patients. A total of 520 patients (317 females, 203 males) developed nausea or vomiting after opioid administration and were randomly assigned to receive a single dose of 1 of 3 study treatments: placebo (n = 94), ondansetron 8 mg (n = 215), or ondansetron 16 mg (n = 211). Ondansetron 8 and 16 mg led to complete control of emesis in 134 of 215 patients (62.3%) and 145 of 211 patients (68.7%), respectively. Results with both doses were significantly better than those seen with placebo (43 of 94 patients [45.7%]). Complete control of nausea was achieved in 6.8% of placebo patients, 14.8% of ondansetron 8-mg-treated patients, and 19.4% of ondansetron 16-mg treated patients; only ondansetron 16 mg was significantly better than placebo (P = 0.007). Significantly more patients who received ondansetron 8 mg than patients who received placebo were satisfied/very satisfied with their antiemetic treatment, as assessed by 4 patient-satisfaction questions. Significantly more patients who received ondansetron 16 mg compared with placebo were satisfied/very satisfied on 2 of 4 satisfaction questions. In conclusion, based on the observed incidence of opioid-induced nausea and vomiting in this study, it may be more appropriate to treat symptoms on occurrence rather than administering antiemetic agents prophylactically. The results of this study demonstrate that intravenous ondansetron in doses of 8 or 16 mg is an effective antiemetic agent for the control of opioid-induced nausea and vomiting in nonsurgical patients requiring opioid analgesia for pain.

Adult↗