Promethazine-induced dystonic reaction

Acute onset of orofacial dystonia from promethazine treatment: A case report

RATIONALE

Promethazine is an antihistamine agent used commonly for nausea and allergy. Along with its anticholinergic and antidopaminergic functions, promethazine is also used for psychiatric symptoms, such as troubling sleep, anxiety, and agitation. Previous studies have reported that promethazine may occasionally elicit acute dystonia in some individuals, especially for young children and pregnant women.

PATIENT CONCERNS

The 68-year-old female patient was admitted to our hospital because of feeling anxious and intermittent palpitation for over 1 year. She developed acute orofacial dystonia following promethazine treatment.

DIAGNOSES

Her diagnoses was generalized anxiety disorder.

INTERVENTIONS

Discontinuation of the offending agent, promethazine, and injection of Botulinum toxin.

OUTCOMES

The acute orofacial dystonia was finally alleviated by local injection of Botulinum toxin.

LESSONS

Careful assessment of the risk of developing acute dystonia is also needed in old patients when initiating the promethazine treatment.

Randomized study of ondansetron versus domperidone in the treatment of children with acute gastroenteritis

Background

Acute gastroenteritis (AGE) is a common condition among children that is frequently accompanied by vomiting. Symptomatic control of vomiting is important as it improves patient’s general condition and reduces the need for intravenous therapy and hospitalization. Antiemetic agents including ondansetron and domperidone are used to provide symptomatic relief but the existing studies do not provide enough evidence of better efficacy for one over another.

Methods

Seventy-six Thai children under the age of 15 with AGE were randomized to receive either ondansetron or domperidone. The primary outcome of the study was the proportion of the patients in each group who had no episode of vomiting 24 hours after the start of treatment.

Results

Primary outcome was met in 62% of patients in ondansetron group and 44% of patients in domperidone group (P = 0.16). Patients in domperidone group received more doses of the drug within 24 hours after the start of the treatment compared to ondansetron group (P = 0.01). No adverse effect was observed in any of the two groups.

Conclusions

Ondansetron can be considered a safe comparable alternative to commonly-used domperidone in Thai children who suffer from symptoms of gastroenteritis. Larger clinical trials are needed to further explore the effectiveness of the two medications.

Use of antiemetics in children with acute gastroenteritis: Are they safe and effective?

The use of antiemetics is a controversial topic in treatment of pediatric gastroenteritis. Although not recommended by the American Academy of Pediatrics, antiemetics are commonly prescribed by physicians. A review of the literature shows side effects of promethazine, prochlorperazine, and metoclopramide are common and potentially dangerous. Ondansetron has recently been studied as an adjunct to oral rehydration therapy in treatment of acute gastroenteritis with mild to moderate dehydration. Although studies are limited, early research suggests the medication is safe when used in a single dose and can be effective to prevent vomiting, the need for intravenous fluids, and hospital admission.

Promethazine overdose: clinical effects, predicting delirium and the effect of charcoal

OBJECTIVE

The aim of this study was to describe the clinical effects of promethazine in overdose and explore the relationship between delirium and possible predictor variables.

METHODS

A case series of promethazine poisonings was identified from a prospective database of poisoning admissions to a regional toxicology service. Data were extracted including demographics, details of ingestion, clinical features including delirium, complications and medical outcomes. In addition to descriptive statistics, a fully Bayesian approach using logistic regression was undertaken to investigate the relationship between predictor variables and delirium.

RESULTS

There were 199 patients with 237 presentations, including 57 patients with 78 promethazine alone overdoses. Of these 57 patients who ingested promethazine alone the median age was 22 years [interquartile range (IQR): 17-31] and 42 were female (74%). The median dose ingested was 625 mg (IQR: 350-1250 mg). Median length of stay was 19 h (IQR: 13-27 h), ten were admitted to the intensive care unit (ICU) and four were ventilated. Delirium occurred in 33 patients (42%), tachycardia (HR>100) occurred on 44 occasions (56%) and hypotension only twice. There were no seizures, dysrhythmias or deaths. Multivariate analysis of 215 presentations (in 181 patients) where dose of promethazine ingested was known demonstrated that dose, administration of charcoal within 2 h and co-ingestants predicted whether patients developed delirium. No relationship was shown for sex and age. A plot of probability that a patient will develop delirium vs. dose was constructed which showed the probability of delirium for 250 mg was 31%, 500 mg was 42% and for 1 g was 55% for promethazine alone overdoses.

CONCLUSION

The main feature of promethazine toxicity is delirium, the probability of which can be predicted from the dose ingested. The administration of charcoal and the presence of co-ingestants appears to reduce the probability of delirium in a predictable manner.

Acute gastroenteritis in children: role of anti-emetic medication for gastroenteritis-related vomiting

Acute gastroenteritis is associated with significant morbidity in developed countries and each year is the cause of death of several million children in developing countries. Acute gastroenteritis is usually self-limiting. Oral rehydration therapy (ORT) is effective and successful in the majority of patients. Vomiting is common at the outset of viral gastroenteritis and can limit the effectiveness of ORT. Treatment with newer anti-emetic medications has been reported to facilitate ORT and to minimize the risk of dehydration and the need for intravenous hydration and hospitalization. The role of anti-emetic medications in the treatment of gastroenteritis-related vomiting is not clear. Some physicians agree with the use of anti-emetic medications because vomiting is unpleasant and distressing for the child and parents alike, and because vomiting can increase the likelihood of dehydration, electrolyte imbalance, and the need for intravenous hydration or hospitalization. Several surveys have shown that anti-emetic medications are commonly prescribed in the treatment of pediatric gastroenteritis and that adverse events are uncommon. Efficacy studies of the newer anti-emetic medications are now available and reveal that some are effective and help facilitate ORT. Other physicians disagree with the use of anti-emetic medications because acute gastroenteritis is a self-limiting condition, vomiting might help rid the body of toxic substances, there was previously a relative lack of published evidence of clinical benefit, and there are potential adverse events associated with the use of an anti-emetic medication. Anti-emetic medications that are currently available include ondansetron, granisetron, tropisetron, dolasetron, ramosetron, promethazine, dimenhydrinate, metoclopramide, domperidone, droperidol, prochlorperazine, and trimethobenzamide. Randomized, placebo-controlled trials suggest that ondansetron is efficacious and superior to other anti-emetic medications in the treatment of gastroenteritis-related vomiting. A recent double-blind clinical trial showed that a single oral dose of ondansetron reduces gastroenteritis-related vomiting and facilitates ORT without significant adverse events. Ondansetron shows promise as a first-line anti-emetic, and judicious use of this agent might increase the success of ORT, minimize the need for intravenous therapy and hospitalization, and reduce healthcare costs. Ondansetron should be considered in situations where vomiting hinders ORT, but a larger randomized, placebo-controlled trial is necessary before the medication can be routinely recommended for the treatment of gastroenteritis-related vomiting in children.

Oral ondansetron for gastroenteritis in a pediatric emergency department

BACKGROUND

Vomiting limits the success of oral rehydration in children with gastroenteritis. We conducted a double-blind trial to determine whether a single oral dose of ondansetron, an antiemetic, would improve outcomes in children with gastroenteritis.

METHODS

We enrolled 215 children 6 months through 10 years of age who were treated in a pediatric emergency department for gastroenteritis and dehydration. After being randomly assigned to treatment with orally disintegrating ondansetron tablets or placebo, the children received oral-rehydration therapy according to a standardized protocol. The primary outcome was the proportion who vomited while receiving oral rehydration. The secondary outcomes were the number of episodes of vomiting and the proportions who were treated with intravenous rehydration or hospitalized.

RESULTS

As compared with children who received placebo, children who received ondansetron were less likely to vomit (14 percent vs. 35 percent; relative risk, 0.40; 95 percent confidence interval, 0.26 to 0.61), vomited less often (mean number of episodes per child, 0.18 vs. 0.65; P<0.001), had greater oral intake (239 ml vs. 196 ml, P=0.001), and were less likely to be treated by intravenous rehydration (14 percent vs. 31 percent; relative risk, 0.46; 95 percent confidence interval, 0.26 to 0.79). Although the mean length of stay in the emergency department was reduced by 12 percent in the ondansetron group, as compared with the placebo group (P=0.02), the rates of hospitalization (4 percent and 5 percent, respectively; P=1.00) and of return visits to the emergency department (19 percent and 22 percent, P=0.73) did not differ significantly between groups.

CONCLUSIONS

In children with gastroenteritis and dehydration, a single dose of oral ondansetron reduces vomiting and facilitates oral rehydration and may thus be well suited for use in the emergency department.

Comparison of Prophylactic Anti-Emetic Effects of Ondansetron and Dexamethasone in Women Undergoing Day-Case Gynaecological Laparoscopic Surgery

We aimed to determine the effect of ondansetron and dexamethasone on preventing post-operative nausea and vomiting (PONV). Sixty women undergoing laparoscopic gynaecological surgery were randomized to receive ondansetron 4 mg, dexamethasone 8 mg or saline. Drugs were administered 2 min before induction of anaesthesia, and anaesthesia and post-operative analgesic regimens were standardized. The incidence of PONV in the first 24 h after the operation was 35% in the ondansetron group, 55% in dexamethasone group and 85% in the control group. A significant difference between the groups was only seen in the first 3 h post-operatively. In this period, ondansetron was significantly more effective than dexamethasone and saline, but no differences were seen between dexamethasone and saline. In all treatment groups, post-operative visual analogue scale scores, sedation scores and usage of analgesics were similar. In conclusion, ondansetron, but not dexamethasone, prevented PONV in the first 3 h after gynaecological laparoscopic surgery.

Antiemetic use in pediatric gastroenteritis: a national survey of emergency physicians, pediatricians, and pediatric emergency physicians

The objective of this study was to review the use of antiemetics for pediatric gastroenteritis and to determine prescribing patterns of physicians. A mailed cross-sectional survey instrument was sent to randomly selected board-certified emergency medicine, pediatric, and pediatric emergency medicine specialists. A total of 1665 surveys were mailed, with 593 completed surveys returned (35.6% response rate). A majority of responders (60.9%) reported using antiemetics for pediatric gastroenteritis at least once in the past year, with a greater than 50% usage for all three specialty groups. Promethazine was the most commonly used antiemetic in all specialties, and per rectum the most common route of administration. Adverse reactions following a single dose of antiemetic were most frequently reported with prochlorperazine. The most common reason for antiemetic use was to prevent further dehydration. The most common concern regarding antiemetic use was potential for side effects. Occasional antiemetic use appears to be a common practice in treating pediatric gastroenteritis, regardless of specialty. Given the absence of literature on efficacy or safety, these drugs should be used only with careful consideration to potential side effects.

A randomized clinical trial comparing oral ondansetron with placebo in children with vomiting from acute gastroenteritis

STUDY OBJECTIVE

Vomiting in children suffering from acute gastroenteritis interferes with the oral rehydration process and equally frustrates parents and health care providers. Adjuncts such as promethazine and metoclopramide are less than optimally effective and are associated with side effects. Ondansetron, a 5-HT3 receptor antagonist marketed as Zofran, is a safe and effective antiemetic used extensively in oncology and postoperative patients. We evaluate the effect of the antiemetic ondansetron versus placebo on the clinical outcome of patients with vomiting from gastroenteritis in a pediatric emergency department.

METHODS

This was a randomized, prospective, double-blind clinical trial in a university-affiliated children's hospital ED. Children between the ages of 6 months and 12 years who had vomited at least 5 times during the preceding 24 hours were randomized to receive either oral ondansetron or a taste- and color-matched placebo. Oral rehydration was commenced 15 minutes later at 5 mL/min per standard oral rehydration protocols. Patients were discharged after they voided and continued standard oral rehydration at home with the introduction of a bananas, rice, applesauce, and toast (BRAT) diet after the first 24 hours. Any patient requiring admission was considered a treatment failure, and no further doses were given. Discharged patients were given 5 additional doses to be used every 8 hours, and they were contacted by telephone 24 and 48 hours after discharge to record the number of episodes of vomiting and diarrhea. The parents were also required to complete a diary of the same information, which was mailed to the investigators for confirmation of the telephone data.

RESULTS

One hundred forty-five patients were enrolled, of whom 51% (n=74) were randomized to ondansetron. At baseline, age distribution, sex, and severity of illness did not differ between the ondansetron and placebo groups. During the observation period in the ED, the median number of episodes of vomiting was 0 in both groups, but the rank sum of vomiting episodes was significantly lower in the ondansetron group (P =.001). The number of episodes of emesis in the ED after enrollment ranged from 0 to 7 in the placebo group and 0 to 2 in the ondansetron group. During the 48 hours of follow-up, the median number of episodes of vomiting remained 0, with no statistically significant difference between the groups. There was no statistically significant difference in the rank sum of episodes of diarrhea in the ED between the groups (P =.622); however, during the next 48 hours, the patients in the ondansetron group had significantly more diarrhea than the placebo group. A lower proportion of patients receiving ondansetron compared with placebo required intravenous fluid therapy (P =.015). The admission rate was also lower in patients receiving ondansetron (P =.007). The revisit rate was higher in the ondansetron group compared with the placebo group (P =.047).

CONCLUSION

Ondansetron was effective in reducing the emesis from gastroenteritis during the ED phase of oral rehydration and in lowering the rates of intravenous fluid administration and hospital admission.

Ondansetron decreases vomiting associated with acute gastroenteritis: a randomized, controlled trial

OBJECTIVE

Relatively little research has examined the role of antiemetic agents in the treatment of acute gastroenteritis. The use of the selective 5-HT3 receptor antagonists (eg, ondansetron) offers a potentially valuable treatment option. The objective of this study was to evaluate the efficacy of ondansetron for the treatment of vomiting associated with acute gastroenteritis in children.

METHODS

A randomized, double blind, placebo-controlled trial was conducted in the emergency department of a tertiary-care children's hospital. Eligible patients were 1 month to 22 years old and required intravenous fluids for gastroenteritis. Of 172 patients approached, 107 were enrolled (54 to intravenous ondansetron, 53 to placebo). The mean age was 5.3 years, and 53% of the patients were male. The frequency of vomiting, admission rate, and occurrence of complications were measured.

RESULTS

After drug administration, 38 (70%) of the 54 patients in the ondansetron group had complete cessation of vomiting compared with 27 (51%) of the 53 patients in the placebo group. Sixteen (30%) of the 53 patients in the placebo group required admission compared with 14 (26%) of the 54 in the ondansetron group. An analysis of previously untreated patients with a measured serum carbon dioxide > or =15 mEq/L showed that 11 (23%) of the 47 who received placebo were admitted compared with 3 (7%) of the 43 who received ondansetron. No significant complications were detected.

CONCLUSIONS

Intravenous ondansetron decreases vomiting in children with gastroenteritis. In addition, ondansetron reduces the need for admission in those who are treated at an initial visit to the emergency department and have a measured serum carbon dioxide > or =15 mEq/L. The safety and low cost of this therapy suggests that ondansetron can be valuable in treating gastroenteritis in children.

Glutaric acidemia, type I, missed by newborn screening in an infant with dystonia following promethazine administration

We report a child initially diagnosed with promethazine-induced dystonia despite a lack of response to diphenhydramine therapy. On further evaluation, the child was diagnosed with glutaric acidemia, type I (GA-I), an autosomal recessive inborn error of metabolism caused by the deficiency of glutaryl-CoA dehydrogenase. The characteristic clinical feature of GA-I is an acute encephalopathic and neurologic crisis typically occurring during a catabolic state. Despite slow improvement, many patients do not fully recover from a neurologic crisis, and residual neurologic morbidity can be significant. Although newborn screening using tandem mass spectrometry is expected to enable presymptomatic diagnosis of GA-I, this patient was not detected by newborn screening with tandem mass spectrometry. Therefore, a high suspicion of GA-I must be maintained in the evaluation of childhood dystonia, even when newborn screening results are reportedly normal.

Pooled analysis of three large clinical trials to determine the optimal dose of dolasetron mesylate needed to prevent postoperative nausea and vomiting. The Dolasetron Prophylaxis Study Group

STUDY OBJECTIVE

To identify the maximally effective dolasetron dose (i.e., maximum efficacy with minimum adverse events) for prevention of postoperative nausea and vomiting (PONV) using the statistical power generated in a pooled patient sample from three large, nearly identical clinical trials.

DESIGN

Three randomized, multicenter, placebo-controlled, double-blinded trials.

SETTING

Trials 1, 2, and 3 enrolled patients at 10, 25, and 17 hospitals and/or surgical centers, respectively.

PATIENTS

A total of 1,946 ASA physical status, I, II, and III patients. Trials 1 and 2 enrolled only female patients (n = 916) undergoing gynecologic surgery. Trial three enrolled 722 females (approximately 70% gynecologic surgeries) and 308 males (approximately 46% orthopedic surgeries) undergoing a variety of surgical procedures.

INTERVENTIONS

All surgical procedures used balanced general anesthesia. Patients received 12.5, 25, 50, or 100 mg of the antiemetic, dolasetron, near the end of anesthesia.

MEASUREMENTS AND MAIN RESULTS

Efficacy endpoints were identical and measured for 24 hours: complete response (no vomiting or rescue medication) and maximum nausea, reported using a 100-mm visual analog scale (VAS). Safety was assessed using adverse event reports, laboratory and electrocardiographic data, and vital signs. All four dolasetron doses produced significant increases in complete response and decreases in maximum VAS nausea compared with placebo (p < 0.01). No increased efficacy was observed with dolasetron doses higher than 12.5 mg. Safety was similar between each dolasetron dose and placebo.

CONCLUSION

Dolasetron 12.5 mg, given near the end of anesthesia, is the maximally effective dose studied for preventing postoperative nausea and vomiting.

The efficacy of RS-25259, a long-acting selective 5-HT3 receptor antagonist, for preventing postoperative nausea and vomiting after hysterectomy procedures

We evaluated the safety and efficacy of RS-25259, a potent and long-acting selective 5-HT3 receptor antagonist, for the prevention of postoperative nausea and vomiting (PONV) in women undergoing hysterectomy procedures. In this randomized, double-blind, placebo controlled, dose-ranging study, 218 healthy, consenting women were assigned to one of the six treatment groups: placebo or RS-25259 0.1, 0.3, 1.0, 3.0, or 30 microg/kg. All patients underwent a standardized general anesthetic technique. The study medication was administered i.v. 20-30 min before the end of surgery. During the initial 24-h period after surgery, the incidence of vomiting, the need for rescue antiemetics, the time to the first episode of emesis, and administration of rescue antiemetic medication, as well as a nausea visual analog scale and verbal categorical scale scores were recorded. In addition, recovery times from the end of anesthesia and the incidences of perioperative side effects were noted. Only 30 microg/kg RS-25259 significantly decreased the incidence of vomiting and the requirement for rescue antiemetics. The largest dose of RS-25259 also delayed the time to the first emetic episode and reduced the number of treatment failures. However, no differences were found in the severity of postoperative nausea (versus saline), and postoperative headaches were more common after the administration of RS-25259 0.3-30 microg/kg i.v. In conclusion, RS-25259 30 microg/kg i.v. was effective in reducing the incidence of PONV after major gynecologic surgery, but the occurrence of headaches with the larger doses of RS-25259 is a concern.

IMPLICATIONS

RS-25259, a long-acting 5-HT3 antagonist, was effective in reducing postoperative vomiting only at the largest dose studied (30 microg/kg). However, RS-25259 had no antinausea activity, and the larger doses were associated with an increased incidence of headaches in the postoperative period.

The effect of timing of ondansetron administration on its efficacy, cost-effectiveness, and cost-benefit as a prophylactic antiemetic in the ambulatory setting

Although ondansetron (4 mg I.V.) is effective in the prevention and treatment of postoperative nausea and vomiting (PONV) after ambulatory surgery, the optimal timing of its administration, the cost-effectiveness, the cost-benefits, and the effect on the patient's quality of life after discharge have not been established. In this placebo-controlled, double-blind study, 164 healthy women undergoing outpatient gynecological laparoscopic procedures with a standardized anesthetic were randomized to receive placebo (Group A), ondansetron 2 mg at the start of and 2 mg after surgery (Group B), ondansetron 4 mg before induction (Group C), or ondansetron 4 mg after surgery (Group D). The effects of these regimens on the incidence, severity, and costs associated with PONV and discharge characteristics were determined, along with the patient's willingness to pay for antiemetics. Compared with ondansetron given before induction of anesthesia, the administration of ondansetron after surgery was associated with lower nausea scores, earlier intake of normal food, decreased incidence of frequent emesis (more than two episodes), and increased times until 25% of patients failed prophylactic antiemetic therapy (i.e., had an emetic episode or received rescue antiemetics for severe nausea) during the first 24 h postoperatively. This prophylactic regimen was also associated with the highest patient satisfaction and lowest cost-effectiveness ratios. Compared with the placebo group, ondansetron administered after surgery significantly reduced the incidence of PONV in the postanesthesia care unit and during the 24-h follow-up period and facilitated the recovery process by reducing the time to oral intake, ambulation, discharge readiness, resuming regular fluid intake and a normal diet. When ondansetron was given as a "split dose," its prophylactic antiemetic efficacy was not significantly different from that of the placebo group. In conclusion, the prophylactic administration of ondansetron after surgery, rather than before induction, may be associated with increased patient benefits.

IMPLICATIONS

Ondansetron 4 mg I.V. administered immediately before the end of surgery was the most efficacious in preventing postoperative nausea and vomiting, facilitating both early and late recovery, and improving patient satisfaction after outpatient laparoscopy.

Intravenous dolasetron and ondansetron in prevention of postoperative nausea and vomiting: a multicenter, double-blind, placebo-controlled study

BACKGROUND

Intravenous dolasetron mesilate has shown efficacy in the prevention of postoperative nausea and vomiting (PONV) when administered as a single dose prior to emergence from anesthesia. This trial compared intravenous dolasetron and ondansetron for the prevention of PONV when administered at induction of anesthesia.

METHODS

This double-blind, placebo-controlled, multicenter trial randomized patients to one of four single IV treatments placebo, 25 or 50 mg dolasetron, or 4 mg ondansetron. Efficacy was measured by complete response (0 emetic episodes and no rescue medication), nausea severity and patient satisfaction as measured on a visual analog scale (VAS), investigator's rating, of nausea severity, and total response (complete response with no nausea [< or = 5 mm VAS]).

RESULTS

514 patients at 24 sites were evaluated for efficacy. The 50 mg dolasetron and 4 mg ondansetron doses were statistically equivalent, and superior to placebo, for all efficacy measures. Complete response rates were 49%, 51%, 71% and 64% for placebo, 25 and 50 mg dolasetron, and ondansetron, respectively. Dolasetron 50 mg was statistically superior to 25 mg dolasetron for complete response, total response, VAS maximum nausea, time to first emetic episode, and patient satisfaction. The majority of adverse events were of mild-to-moderate intensity. Headache was the most frequently reported treatment-related adverse event with a 3%-5% incidence across treatments.

CONCLUSION

When given at induction of anesthesia, 50 mg intravenous dolasetron is equivalent to 4 mg ondansetron and superior to 25 mg dolasetron and placebo for the prevention of PONV. All treatments were safely administered and well tolerated.

Vomiting and retching in Gilles de la Tourette syndrome: a report of ten cases and a review of the literature

Retching and vomiting are common symptoms in childhood. We describe the cases of 10 patients with Gilles de la Tourette syndrome (GTS) for whom vomiting or retching tics were part of the clinical picture, and discuss other instances where retching and vomiting occur with neuropsychiatric or movement disorders.

Comparison of tropisetron, droperidol, and saline in the prevention of postoperative nausea and vomiting after gynecologic surgery

This study was performed to compare the efficacy of tropisetron, droperidol, and saline in the prevention of postoperative nausea and vomiting (PONV) and to compare the possible adverse effects of these drugs in gynecologic incontinence surgery. Using a randomized, double-blind study design, we studied 150 women undergoing gynecologic incontinence surgery with standardized general anesthesia. At the end of surgery, the patients received either tropisetron 5 mg, droperidol 1.25 mg, or 0.9% saline intravenously (i.v.). As a rescue antiemetic, the patients received metoclopramide 10 mg i.v.. The episodes of nausea, retching, and vomiting; the need for rescue treatment; and the type and severity of adverse events were recorded at four occasions during the 48-h observation period. Pain, anxiety, drowsiness, and general satisfaction were also evaluated on a linear numerical scale of 0-10. Complete response (no PONV within the 48-h observation period) occurred similarly in the study groups (tropisetron 25%, droperidol 22%, and placebo 18%). Tropisetron and droperidol had no effect on the incidence of nausea and retching. However, the incidence of vomiting was significantly less in the tropisetron group than in the placebo group (tropisetron 19%, droperidol 45%, and placebo 57%). The number of emetic episodes (retching and/or vomiting) per patient within 48 h was significantly decreased under tropisetron when compared with placebo (tropisetron 2.5 +/- 3.4, droperidol 4.2 +/- 6.1, placebo 5.9 +/- 7.1). With regard to adverse events, the patients in the droperidol group had significantly more anxiety than the placebo group (2-6 h postoperatively), more drowsiness than the tropisetron and placebo groups (0-2 h postoperatively), and more dissatisfaction than the tropisetron (0-6 h postoperatively) and placebo groups (2-6 h postoperatively). We conclude that tropisetron given 5 mg i.v. during anesthesia in gynecologic incontinence surgery effectively prevents vomiting but not nausea and retching, while 1.25 mg i.v. droperidol fails to prevent any of these emetic symptoms and results in adverse events.

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.

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.