Dexamethasone vs Ondansetron After Cesarean Delivery

Dexamethasone vs Ondansetron as the First-line Antiemetic to Prevent Postoperative Nausea and Vomiting After Cesarean Delivery

The goal of this clinical trial is to compare medications in women having a cesarean delivery. The main question it aims to answer are:

• Which medication is better to use as a first-line prevention agent for nausea and vomiting Participants will rate their nausea, pain and other symptoms after surgery Researchers will compare two drugs, ondansetron and dexamethasone to see if the side effects of pain medications are improved after cesarean.

Study Overview

• Status: Completed
• Conditions: Cesarean Section Complications; Nausea and Vomiting, Postoperative
• Intervention / Treatment: Drug: Ondansetron; Drug: Dexamethasone

Detailed Description

Cesarean delivery is the most common surgical procedure performed in the United States, with approximately 1.2 million cesarean deliveries performed in 2020.(1) Cesarean delivery is preferentially performed under neuraxial anesthesia (spinal or epidural anesthesia) to allow mothers to be awake during the delivery of their child and to improve maternal safety. Despite the routine use of neuraxial techniques for most cesarean deliveries in the United States, many patients experience nausea and/or vomiting either during surgery (intraoperative nausea and vomiting, IONV) or after surgery (postoperative nausea and vomiting, PONV).

PONV has traditionally been associated with female gender, history of motion sickness, nonsmoking status, and opioid use.(2) Other authors have shown increased PONV risk with younger age, type of surgery, and general anesthesia as opposed to regional or neuraxial anesthesia.(3,4) Intrathecal opioids, are the gold standard for pain relief after cesarean delivery, and are part of the Society for Obstetric Anesthesia and Perinatology's (SOAP) Early Recover After Cesarean (ERAC) guideline. However, these medications have been implicated in increased rates of PONV.(5) Given the prevalence of cesarean delivery and the importance of maternal well-being, prophylaxis of nausea and vomiting remains an important issue to address.

Medications from multiple classes are commonly administered to prevent and treat PONV after cesarean delivery. These include 5-HT3 antagonists, dopaminergic antagonists, corticosteroids, antihistamines, and anticholinergics. Ondansetron, a 5HT3 antagonist, and dexamethasone, a corticosteroid, are among the most commonly administered medications due to their efficacy and long track record of safety during pregnancy. Indeed, the SOAP ERAC guideline recommends that at least two agents from different classes be administered perioperatively to decrease the rates of IONV and PONV.(6) They further suggest metoclopramide for IONV prophylaxis, ondansetron or dexamethasone for PONV prophylaxis.

The safety and efficacy of ondansetron and dexamethasone are further supported by a 2021 Cochrane Systematic review analyzing medical prophylaxis against IONV and PONV in cesarean delivery.(6) Both ondansetron and dexamethasone decreased postoperative nausea (Ond: RR 0.45; 10 RCT, 1340 total subjects; Dex: RR 0.59; 6 studies, 733 women) and vomiting rates (Ond: RR 0.47, 10 studies, 1450 women; Dex: RR 0.68; 7 RCT, 793 women). No adverse events from 5HT3 blocking agents or corticosteroids were identified.

Dexamethasone is intriguing as a first-line agent for cesarean delivery since it may have the added benefit of improved pain control and/or decreased postoperative opioid requirement. Several studies have addressed the role of dexamethasone in pain management. A 2008 study by Jaafarpour et al.(8) found a decrease in composite rates of nausea and vomiting, as well reduction of ~1 point on the VAS pain scale for 24 hours following surgery. Data from other studies have been mixed (9, 10, 11).

In conclusion, there is a gap in knowledge in defining the optimal first-line antiemetic for prophylaxis of PONV in patients undergoing cesarean delivery. The goal of this study is to evaluate the effectiveness of ondansetron vs. dexamethasone on PONV rates and postoperative pain control.

• Study Type: Interventional
• Enrollment (Actual): 100
• Phase: Phase 4

Contacts and Locations

Study Locations

• United States
  • Massachusetts
    • Boston, Massachusetts, United States, 02215
      • Beth Israel Deaconess Medical Center

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 45 years (Adult)
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Healthy women (ASA 2)
• Between 18 and 45 years old
• Singleton term pregnancies
• Scheduled or non-labor cesarean delivery
• Neuraxial (spinal or combined-spinal epidural) anesthesia

Exclusion Criteria:

• Refusal to participate
• Known allergy or contraindication to any medication used in the study
• Significant medical or obstetrical disease (ASA ≥ 3)
• Antiemetic use within 24 hours preceding cesarean delivery
• Insulin dependent diabetes
• Hyperemesis gravidarum or chronic antiemetic use
• History of daily or near-daily steroid use during pregnancy
• Opioid use disorder or other chronic pain syndrome
• Opioid use during pregnancy
• Use of antipruritus medication, pruritic urticarial papules of pregnancy, or cholestasis of pregnancy

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Quadruple

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Ondansetron; ondansetron 4 mg intravenous, given once after initiation of anesthesia	Drug: Ondansetron; Administered Medication
Active Comparator: Dexamethasone; dexamethasone 8 mg intravenous, given once after initiation of anesthesia	Drug: Dexamethasone; Administered Medication

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Medications Received	Total number of unscheduled medications administered by nurses to patients and received in the 24 hours after cesarean for the treatment of Nausea, vomiting, pruritus or pain	24 hours

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Severity of Nausea	Visual analogue score for Nausea scored on a 10 centimeter line with "No nausea" on the left and "Worst possible nausea" on the right. The minimum score was 0, maximum score was 10, with higher scores represent greater nausea.	24 hours
Severity of Pain	Visual analogue score for Pain scored on a 10 centimeter line with "No pain" on the left and "Worst possible pain" on the right. The minimum score was 0, maximum score was 10, with higher scores represent greater pain.	24 hours

Collaborators and Investigators

• Sponsor: Beth Israel Deaconess Medical Center

Study record dates

Study Major Dates

• Study Start (Actual): March 30, 2023
• Primary Completion (Actual): April 30, 2024
• Study Completion (Actual): April 30, 2024

Study Registration Dates

• First Submitted: January 11, 2023
• First Submitted That Met QC Criteria: January 11, 2023
• First Posted (Actual): January 20, 2023

Study Record Updates

• Last Update Posted (Actual): March 13, 2026
• Last Update Submitted That Met QC Criteria: February 23, 2026
• Last Verified: February 1, 2026

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Postoperative Complications; Pathologic Processes; Signs and Symptoms, Digestive; Vomiting; Nausea; Pathological Conditions, Signs and Symptoms; Signs and Symptoms; Postoperative Nausea and Vomiting; Heterocyclic Compounds, 1-Ring; Heterocyclic Compounds; Heterocyclic Compounds, 2-Ring; Heterocyclic Compounds, Fused-Ring; Azoles; Polycyclic Compounds; Imidazoles; Indoles; Pregnadienes; Pregnanes; Steroids; Fused-Ring Compounds; Steroids, Fluorinated; Pregnadienetriols; Heterocyclic Compounds, 3-Ring; Carbazoles; Dexamethasone; Ondansetron
• Other Study ID Numbers: 2023P000019

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No