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Zofran Injection

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Zofran Injection




CLINICAL PHARMACOLOGY

Mechanism Of Action

Ondansetron is a selective 5-HT3 receptor antagonist. While ondansetron’s mechanism of action has not been fully characterized, it is not a dopamine-receptor antagonist.

Pharmacodynamics

QTc interval prolongation was studied in a double-blind, single intravenous dose, placebo- and positive-controlled, crossover trial in 58 healthy subjects. The maximum mean (95% upper confidence bound) difference in QTcF from placebo after baseline correction was 19.5 (21.8) ms and 5.6 (7.4) ms after 15-minute intravenous infusions of 32 mg and 8 mg ZOFRAN, respectively. A significant exposure-response relationship was identified between ondansetron concentration and ΔΔQTcF. Using the established exposure-response relationship, 24 mg infused intravenously over 15 minutes had a mean predicted (95% upper prediction interval) ΔΔQTcF of 14.0 (16.3) ms. In contrast, 16 mg infused intravenously over 15 minutes using the same model had a mean predicted (95% upper prediction interval) ΔΔQTcF of 9.1 (11.2) ms.

In normal volunteers, single intravenous doses of 0.15 mg/kg of ondansetron had no effect on esophageal motility, gastric motility, lower esophageal sphincter pressure, or small intestinal transit time. In another trial in six normal male volunteers, a 16-mg dose infused over 5 minutes showed no effect of the drug on cardiac output, heart rate, stroke volume, blood pressure, or electrocardiogram (ECG). Multiday administration of ondansetron has been shown to slow colonic transit in normal volunteers. Ondansetron has no effect on plasma prolactin concentrations. In a gender-balanced pharmacodynamic trial (n = 56), ondansetron 4 mg administered intravenously or intramuscularly was dynamically similar in the prevention of nausea and vomiting using the ipecacuanha model of emesis.

Pharmacokinetics

In normal adult volunteers, the following mean pharmacokinetic data have been determined following a single 0.15-mg/kg intravenous dose.

Table 3. Pharmacokinetics in Normal Adult Volunteers

Age-group
(years)
n Peak Plasma Concentration
(ng/mL)
Mean Elimination Half-life (h) Plasma Clearance
(L/h/kg)
19-40 11 102 3.5 0.381
61-74 12 106 4.7 0.319
≥75 11 170 5.5 0.262

Absorption

A trial was performed in normal volunteers (n = 56) to evaluate the pharmacokinetics of a single 4-mg dose administered as a 5-minute infusion compared with a single intramuscular injection. Systemic exposure as measured by mean AUC were equivalent, with values of 156 [95% CI: 136, 180] and 161 [95% CI: 137, 190] ng•h/mL for intravenous and intramuscular groups, respectively. Mean peak plasma concentrations were 42.9 [95% CI: 33.8, 54.4] ng/mL at 10 minutes after intravenous infusion and 31.9 [95% CI: 26.3, 38.6] ng/mL at 41 minutes after intramuscular injection.

Distribution

Plasma protein binding of ondansetron as measured in vitro was 70% to 76%, over the pharmacologic concentration range of 10 to 500 ng/mL. Circulating drug also distributes into erythrocytes.

Metabolism

Ondansetron is extensively metabolized in humans, with approximately 5% of a radiolabeled dose recovered as the parent compound from the urine. The primary metabolic pathway is hydroxylation on the indole ring followed by subsequent glucuronide or sulfate conjugation.

Although some nonconjugated metabolites have pharmacologic activity, these are not found in plasma at concentrations likely to significantly contribute to the biological activity of ondansetron. The metabolites are observed in the urine.

In vitro metabolism studies have shown that ondansetron is a substrate for multiple human hepatic cytochrome P-450 enzymes, including CYP1A2, CYP2D6, and CYP3A4. In terms of overall ondansetron turnover, CYP3A4 plays a predominant role while formation of the major in vivo metabolites is apparently mediated by CYP1A2. The role of CYP2D6 in ondansetron in vivo metabolism is relatively minor.

The pharmacokinetics of intravenous ondansetron did not differ between subjects who were poor metabolizers of CYP2D6 and those who were extensive metabolizers of CYP2D6, further supporting the limited role of CYP2D6 in ondansetron disposition in vivo.

Elimination

In adult cancer patients, the mean ondansetron elimination half-life was 4.0 hours, and there was no difference in the multidose pharmacokinetics over a 4-day period. In a dose-proportionality trial, systemic exposure to 32 mg of ondansetron was not proportional to dose as measured by comparing dose-normalized AUC values with an 8-mg dose. This is consistent with a small decrease in systemic clearance with increasing plasma concentrations.

Geriatrics

A reduction in clearance and increase in elimination half-life are seen in patients over 75 years of age. In clinical trials with cancer patients, safety and efficacy were similar in patients over 65 years of age and those under 65 years of age; there was an insufficient number of patients over 75 years of age to permit conclusions in that age-group. No dosage adjustment is recommended in the elderly.

Pediatrics

Pharmacokinetic samples were collected from 74 cancer patients aged 6 to 48 months, who received a dose of 0.15 mg/kg of intravenous ondansetron every 4 hours for 3 doses during a safety and efficacy trial. These data were combined with sequential pharmacokinetics data from 41 surgery patients aged 1 month to 24 months, who received a single dose of 0.1 mg/kg of intravenous ondansetron prior to surgery with general anesthesia, and a population pharmacokinetic analysis was performed on the combined data set. The results of this analysis are included in Table 4 and are compared with the pharmacokinetic results in cancer patients aged 4 to 18 years.

Table 4. Pharmacokinetics in Pediatric Cancer Patients Aged 1 Month to 18 Years

Subjects and Age-group N CL
(L/h/kg)
Vdss
(L/kg)

(h)
Geometric Mean Mean
Pediatric Cancer Patients
4 to 18 years
N = 21 0.599 1.9 2.8
Population PK Patientsa
1 month to 48 months
N = 115 0.582 3.65 4.9
a Population PK (Pharmacokinetic) Patients: 64% cancer patients and 36% surgery patients.

Based on the population pharmacokinetic analysis, cancer patients aged 6 to 48 months who receive a dose of 0.15 mg/kg of intravenous ondansetron every 4 hours for 3 doses would be expected to achieve a systemic exposure (AUC) consistent with the exposure achieved in previous pediatric trials in cancer patients (4 to 18 years) at similar doses.

In a trial of 21 pediatric patients (3 to 12 years) who were undergoing surgery requiring anesthesia for a duration of 45 minutes to 2 hours, a single intravenous dose of ondansetron, 2 mg (3 to 7 years) or 4 mg (8 to 12 years), was administered immediately prior to anesthesia induction. Mean weight-normalized clearance and volume of distribution values in these pediatric surgical patients were similar to those previously reported for young adults. Mean terminal half-life was slightly reduced in pediatric patients (range: 2.5 to 3 hours) in comparison with adults (range: 3 to 3.5 hours).

In a trial of 51 pediatric patients (aged 1 month to 24 months) who were undergoing surgery requiring general anesthesia, a single intravenous dose of ondansetron, 0.1 or 0.2 mg/kg, was administered prior to surgery. As shown in Table 5, the 41 patients with pharmacokinetic data were divided into 2 groups, patients aged 1 month to 4 months and patients aged 5 to 24 months, and are compared with pediatric patients aged 3 to 12 years.

Table 5. Pharmacokinetics in Pediatric Surgery Patients Aged 1 Month to 12 Years

Subjects and Age-group N CL
(L/h/kg)
Vdss
(L/kg)

(h)
Geometric Mean Mean
Pediatric Surgery Patients
3 to 12 years
N = 21 0.439 1.65 2.9
Pediatric Surgery Patients
5 to 24 months
N = 22 0.581 2.3 2.9
Pediatric Surgery Patients
1 month to 4 months
N = 19 0.401 3.5 6.7

In general, surgical and cancer pediatric patients younger than 18 years tend to have a higher ondansetron clearance compared with adults leading to a shorter half-life in most pediatric patients. In patients aged 1 month to 4 months, a longer half-life was observed due to the higher volume of distribution in this age-group.

In a trial of 21 pediatric cancer patients (aged 4 to 18 years) who received three intravenous doses of 0.15 mg/kg of ondansetron at 4-hour intervals, patients older than 15 years exhibited ondansetron pharmacokinetic parameters similar to those of adults.

Renal Impairment

Due to the very small contribution (5%) of renal clearance to the overall clearance, renal impairment was not expected to significantly influence the total clearance of ondansetron. However, ondansetron mean plasma clearance was reduced by about 41% in patients with severe renal impairment (creatinine clearance <30 mL/min). This reduction in clearance is variable and was not consistent with an increase in half-life. No reduction in dose or dosing frequency in these patients is warranted.

Hepatic Impairment

In patients with mild-to-moderate hepatic impairment, clearance is reduced 2-fold and mean half-life is increased to 11.6 hours compared with 5.7 hours in those without hepatic impairment.

In patients with severe hepatic impairment (Child-Pugh score of 10 or greater), clearance is reduced 2-fold to 3-fold and apparent volume of distribution is increased with a resultant increase in half-life to 20 hours. In patients with severe hepatic impairment, a total daily dose of 8 mg should not be exceeded.

Clinical Studies

The clinical efficacy of ondansetron hydrochloride, the active ingredient of ZOFRAN, was assessed in clinical trials as described below.

Chemotherapy-Induced Nausea And Vomiting

Adults

In a double-blind trial of three different dosing regimens of ZOFRAN Injection, 0.015 mg/kg, 0.15 mg/kg, and 0.30 mg/kg, each given three times during the course of cancer chemotherapy, the 0.15-mg/kg dosing regimen was more effective than the 0.015-mg/kg dosing regimen. The 0.30-mg/kg dosing regimen was not shown to be more effective than the 0.15-mg/kg dosing regimen.

Cisplatin-based Chemotherapy

In a double-blind trial in 28 patients, ZOFRAN Injection (three 0.15-mg/kg doses) was significantly more effective than placebo in preventing nausea and vomiting induced by cisplatin-based chemotherapy. Therapeutic response was as shown in Table 6.

Table 6. Therapeutic Response in Prevention of Chemotherapy-induced Nausea and Vomiting in Single-day Cisplatin Therapya in Adults

  ZOFRAN Injection
(0.15 mg/kg x 3)
Placebo P Valueb
Number of patients 14 14  
Treatment response      
  0 Emetic episodes 2 (14%) 0 (0%)  
  1-2 Emetic episodes 8 (57%) 0 (0%)  
  3-5 Emetic episodes 2 (14%) 1 (7%)  
  More than 5 emetic episodes/rescued 2 (14%) 13 (93%) 0.001
Median number of emetic episodes 1.5 Undefinedc  
Median time to first emetic episode (h) 11.6 2.8 0.001
Median nausea scores (0-100)d 3 59 0.034
Global satisfaction with control of nausea and vomiting (0-100)e 96 10.5 0.009
a Chemotherapy was high dose (100 and 120 mg/m2; ZOFRAN Injection n = 6, placebo n = 5) or moderate dose (50 and 80 mg/m2; ZOFRAN Injection n = 8, placebo n = 9). Other chemotherapeutic agents included fluorouracil, doxorubicin, and cyclophosphamide. There was no difference between treatments in the types of chemotherapy that would account for differences in response.
b Efficacy based on "all-patients-treated" analysis.
c Median undefined since at least 50% of the patients were rescued or had more than five emetic episodes.
d Visual analog scale assessment of nausea: 0 = no nausea, 100 = nausea as bad as it can be.
e Visual analog scale assessment of satisfaction: 0 = not at all satisfied, 100 = totally satisfied.

Ondansetron injection (0.15-mg/kg x 3 doses) was compared with metoclopramide (2 mg/kg x 6 doses) in a single-blind trial in 307 patients receiving cisplatin ≥100 mg/m2 with or without other chemotherapeutic agents. Patients received the first dose of ondansetron or metoclopramide 30 minutes before cisplatin. Two additional ondansetron doses were administered 4 and 8 hours later, or five additional metoclopramide doses were administered 2, 4, 7, 10, and 13 hours later. Cisplatin was administered over a period of 3 hours or less. Episodes of vomiting and retching were tabulated over the period of 24 hours after cisplatin. The results of this trial are summarized in Table 7.

Table 7. Therapeutic Response in Prevention of Vomiting Induced by Cisplatin (≥100 mg/m2) Single-day Therapya in Adults

  ZOFRAN Injection
0.15 mg/kg x 3
Metoclopramide
2 mg/kg x 6
P Value
Number of patients in efficacy population 136 138  
Treatment response      
  0 Emetic episodes 54 (40%) 41 (30%)  
  1-2 Emetic episodes 34 (25%) 30 (22%)  
  3-5 Emetic episodes 19 (14%) 18 (13%)  
  More than 5 emetic episodes/rescued 29 (21%) 49 (36%)  
Comparison of treatments with respect to      
  0 Emetic episodes 54/136 41/138 0.083
  More than 5 emetic episodes/rescued 29/136 49/138 0.009
Median number of emetic episodes 1 2 0.005
Median time to first emetic episode (h) 20.5 4.3 <0.001
Global satisfaction with control of nausea and vomiting (0-100)b 85 63 0.001
Acute dystonic reactions 0 8 0.005
Akathisia 0 10 0.002
a In addition to cisplatin, 68% of patients received other chemotherapeutic agents, including cyclophosphamide, etoposide, and fluorouracil. There was no difference between treatments in the types of chemotherapy that would account for differences in response.
b Visual analog scale assessment: 0 = not at all satisfied, 100 = totally satisfied.

Cyclophosphamide-based Chemotherapy

In a double-blind, placebo-controlled trial of ZOFRAN Injection (three 0.15-mg/kg doses) in 20 patients receiving cyclophosphamide (500 to 600 mg/m2) chemotherapy, ZOFRAN Injection was significantly more effective than placebo in preventing nausea and vomiting. The results are summarized in Table 8.

Table 8. Therapeutic Response in Prevention of Chemotherapy-induced Nausea and Vomiting in Single-day Cyclophosphamide Therapya in Adults

  ZOFRAN Injection
(0.15 mg/kg x 3)
Placebo P Valueb
Number of patients 10 10  
Treatment response      
  0 Emetic episodes 7 (70%) 0 (0%) 0.001
  1-2 Emetic episodes 0 (0%) 2 (20%)  
  3-5 Emetic episodes 2 (20%) 4 (40%)  
  More than 5 emetic episodes/rescued 1 (10%) 4 (40%) 0.131
Median number of emetic episodes 0 4 0.008
Median time to first emetic episode (h) Undefinedc 8.79  
Median nausea scores (0-100)d 0 60 0.001
Global satisfaction with control of nausea and vomiting (0-100)e 100 52 0.008
a Chemotherapy consisted of cyclophosphamide in all patients, plus other agents, including fluorouracil, doxorubicin, methotrexate, and vincristine. There was no difference between treatments in the type of chemotherapy that would account for differences in response.
b Efficacy based on "all-patients-treated" analysis.
c Median undefined since at least 50% of patients did not have any emetic episodes.
d Visual analog scale assessment of nausea: 0 = no nausea, 100 = nausea as bad as it can be.
e Visual analog scale assessment of satisfaction: 0 = not at all satisfied, 100 = totally satisfied.

Re-treatment

In uncontrolled trials, 127 patients receiving cisplatin (median dose, 100 mg/m2) and ondansetron who had two or fewer emetic episodes were re-treated with ondansetron and chemotherapy, mainly cisplatin, for a total of 269 re-treatment courses (median: 2; range: 1 to 10). No emetic episodes occurred in 160 (59%), and two or fewer emetic episodes occurred in 217 (81%) re-treatment courses.

Pediatrics

Four open-label, noncomparative (one US, three foreign) trials have been performed with 209 pediatric cancer patients aged 4 to 18 years given a variety of cisplatin or noncisplatin regimens. In the three foreign trials, the initial dose of ZOFRAN Injection ranged from 0.04 to 0.87 mg/kg for a total dose of 2.16 to 12 mg. This was followed by the oral administration of ondansetron ranging from 4 to 24 mg daily for 3 days. In the US trial, ZOFRAN was administered intravenously (only) in three doses of 0.15 mg/kg each for a total daily dose of 7.2 to 39 mg. In these trials, 58% of the 196 evaluable patients had a complete response (no emetic episodes) on Day 1. Thus, prevention of vomiting in these pediatric patients was essentially the same as for patients older than 18 years.

An open-label, multicenter, noncomparative trial has been performed in 75 pediatric cancer patients aged 6 to 48 months receiving at least one moderately or highly emetogenic chemotherapeutic agent. Fifty-seven percent (57%) were females; 67% were white, 18% were American Hispanic, and 15% were black patients. ZOFRAN was administered intravenously over 15 minutes in three doses of 0.15 mg/kg. The first dose was administered 30 minutes before the start of chemotherapy; the second and third doses were administered 4 and 8 hours after the first dose, respectively. Eighteen patients (25%) received routine prophylactic dexamethasone (i.e., not given as rescue). Of the 75 evaluable patients, 56% had a complete response (no emetic episodes) on Day 1. Thus, prevention of vomiting in these pediatric patients was comparable to the prevention of vomiting in patients aged 4 years and older.

Prevention Of Postoperative Nausea And/Or Vomiting

Adults

Adult surgical patients who received ondansetron immediately before the induction of general balanced anesthesia (barbiturate: thiopental, methohexital, or thiamylal; opioid: alfentanil or fentanyl; nitrous oxide; neuromuscular blockade: succinylcholine/curare and/or vecuronium or atracurium; and supplemental isoflurane) were evaluated in two double-blind US trials involving 554 patients. ZOFRAN Injection (4 mg) intravenous given over 2 to 5 minutes was significantly more effective than placebo. The results of these trials are summarized in Table 9.

Table 9. Therapeutic Response in Prevention of Postoperative Nausea and Vomiting in Adult Patients

  Ondansetron
4 mg
Intravenous
Placebo P Value
Study 1      
Emetic episodes:      
Number of patients 136 139  
Treatment response over 24-h postoperative period      
  0 Emetic episodes 103 (76%) 64 (46%) <0.001
  1 Emetic episode 13 (10%) 17 (12%)  
  More than 1 emetic episode/rescued 20 (15%) 58 (42%)  
Nausea assessments:      
Number of patients 134 136  
No nausea over 24-h postoperative period 56 (42%) 39 (29%)  
Study 2      
Number of patients 136 143  
Treatment response over 24-h postoperative period      
  0 Emetic episodes 85 (63%) 63 (44%) 0.002
  1 Emetic episode 16 (12%) 29 (20%)  
  More than 1 emetic episode/rescued 35 (26%) 51 (36%)  
Nausea assessments:      
Number of patients 125 133  
No nausea over 24-h postoperative period 48 (38%) 42 (32%)  

The populations in Table 9 consisted mainly of females undergoing laparoscopic procedures.

In a placebo-controlled trial conducted in 468 males undergoing outpatient procedures, a single 4-mg intravenous ondansetron dose prevented postoperative vomiting over a 24-hour period in 79% of males receiving drug compared with 63% of males receiving placebo (P <0.001).

Two other placebo-controlled trials were conducted in 2,792 patients undergoing major abdominal or gynecological surgeries to evaluate a single 4-mg or 8-mg intravenous ondansetron dose for prevention of postoperative nausea and vomiting over a 24-hour period. At the 4-mg dosage, 59% of patients receiving ondansetron versus 45% receiving placebo in the first trial (P <0.001) and 41% of patients receiving ondansetron versus 30% receiving placebo in the second trial (P = 0.001) experienced no emetic episodes. No additional benefit was observed in patients who received intravenous ondansetron 8 mg compared with patients who received intravenous ondansetron 4 mg.

Pediatrics

Three double-blind, placebo-controlled trials have been performed (one US, two foreign) in 1,049 male and female patients (aged 2 to 12 years) undergoing general anesthesia with nitrous oxide. The surgical procedures included tonsillectomy with or without adenoidectomy, strabismus surgery, herniorrhaphy, and orchidopexy. Patients were randomized to either single intravenous doses of ondansetron (0.1 mg/kg for pediatric patients weighing 40 kg or less, 4 mg for pediatric patients weighing more than 40 kg) or placebo. Study drug was administered over at least 30 seconds, immediately prior to or following anesthesia induction. Ondansetron was significantly more effective than placebo in preventing nausea and vomiting. The results of these trials are summarized in Table 10.

Table 10. Therapeutic Response in Prevention of Postoperative Nausea and Vomiting in Pediatric Patients Aged 2 to 12 Years

Treatment Response Over 24 Hours Ondansetron
n (%)
Placebo
n (%)
P Value
Study 1      
Number of patients 205 210  
0 Emetic episodes 140 (68%) 82 (39%) ≤0.001
Failurea 65 (32%) 128 (61%)  
Study 2      
Number of patients 112 110  
0 Emetic episodes 68 (61%) 38 (35%) ≤0.001
Failurea 44 (39%) 72 (65%)  
Study 3      
Number of patients 206 206  
0 Emetic episodes 123 (60%) 96 (47%) ≤0.01
Failurea 83 (40%) 110 (53%)  
Nausea assessmentsb:      
Number of patients 185 191  
None 119 (64%) 99 (52%) ≤0.01
a Failure was one or more emetic episodes, rescued, or withdrawn.
b Nausea measured as none, mild, or severe.

A double-blind, multicenter, placebo-controlled trial was conducted in 670 pediatric patients aged 1 month to 24 months who were undergoing routine surgery under general anesthesia. Seventy-five percent (75%) were males; 64% were white, 15% were black, 13% were American Hispanic, 2% were Asian, and 6% were “other race” patients. A single 0.1-mg/kg intravenous dose of ondansetron administered within 5 minutes following induction of anesthesia was statistically significantly more effective than placebo in preventing vomiting. In the placebo group, 28% of patients experienced vomiting compared with 11% of subjects who received ondansetron (P ≤0.01). Overall, 32 (10%) of placebo patients and 18 (5%) of patients who received ondansetron received antiemetic rescue medication(s) or prematurely withdrew from the trial.

Prevention Of Further Postoperative Nausea And Vomiting

Adults

Adult surgical patients receiving general balanced anesthesia (barbiturate: thiopental, methohexital, or thiamylal; opioid: alfentanil or fentanyl; nitrous oxide; neuromuscular blockade: succinylcholine/curare and/or vecuronium or atracurium; and supplemental isoflurane) who received no prophylactic antiemetics and who experienced nausea and/or vomiting within 2 hours postoperatively were evaluated in two double-blind US trials involving 441 patients. Patients who experienced an episode of postoperative nausea and/or vomiting were given ZOFRAN Injection (4 mg) intravenously over 2 to 5 minutes, and this was significantly more effective than placebo. The results of these trials are summarized in Table 11.

Table 11. Therapeutic Response in Prevention of Further Postoperative Nausea and Vomiting in Adult Patients

  Ondansetron
4 mg
Intravenous
Placebo P Value
Study 1      
Emetic episodes:      
Number of patients 104 117  
Treatment response 24 h after study drug      
  0 Emetic episodes 49 (47%) 19 (16%) <0.001
  1 Emetic episode 12 (12%) 9 (8%)  
  More than 1 emetic episode/rescued 43 (41%) 89 (76%)  
Median time to first emetic episode (min)a 55.0 43.0  
Nausea assessments:      
Number of patients 98 102  
Mean nausea score over 24-h postoperative periodb 1.7 3.1  
Study 2      
Emetic episodes:      
Number of patients 112 108  
Treatment response 24 h after study drug      
  0 Emetic episodes 49 (44%) 28 (26%) 0.006
  1 Emetic episode 14 (13%) 3 (3%)  
  More than 1 emetic episode/rescued 49 (44%) 77 (71%)  
Median time to first emetic episode (min)a 60.5 34.0  
Nausea assessments:      
Number of patients 105 85  
Mean nausea score over 24-h postoperative periodb 1.9 2.9  
a After administration of study drug.
b Nausea measured on a scale of 0-10 with 0 = no nausea, 10 = nausea as bad as it can be.

The populations in Table 11 consisted mainly of women undergoing laparoscopic procedures.

Repeat Dosing in Adults

In patients who do not achieve adequate control of postoperative nausea and vomiting following a single, prophylactic, preinduction, intravenous dose of ondansetron 4 mg, administration of a second intravenous dose of ondansetron 4 mg postoperatively does not provide additional control of nausea and vomiting.

Pediatrics

One double-blind, placebo-controlled, US trial was performed in 351 male and female outpatients (aged 2 to 12 years) who received general anesthesia with nitrous oxide and no prophylactic antiemetics. Surgical procedures were unrestricted. Patients who experienced two or more emetic episodes within 2 hours following discontinuation of nitrous oxide were randomized to either single intravenous doses of ondansetron (0.1 mg/kg for pediatric patients weighing 40 kg or less, 4 mg for pediatric patients weighing more than 40 kg) or placebo administered over at least 30 seconds. Ondansetron was significantly more effective than placebo in preventing further episodes of nausea and vomiting. The results of the trial are summarized in Table 12.

Table 12. Therapeutic Response in Prevention of Further Postoperative Nausea and Vomiting in Pediatric Patients Aged 2 to 12 Years

Treatment Response Over 24 Hours Ondansetron
n (%)
Placebo
n (%)
P Value
Number of patients 180 171 ≤0.001
0 Emetic episodes 96 (53%) 29 (17%)  
Failurea 84 (47%) 142 (83%)  
a Failure was one or more emetic episodes, rescued, or withdrawn.

Last reviewed on RxList: 11/16/2016
This monograph has been modified to include the generic and brand name in many instances.

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