Oral Ondansetron to Improve Patient Experience of Unsedated Esophagogastroduodenoscopy Pilot Study

Oral Ondansetron to Improve Patient Experience of Unsedated Esophagogastroduodenoscopy: A Pilot Study

The goal of this interventional pilot study is to explore the feasibility of administering ondansetron prior to esophagogastroduodenoscopy (EGD), and preliminarily test if it can alleviate the gagging reflex, nausea and vomiting in Chinese patients undergoing unsedated diagnostic EGD. The main questions it aims to answer are:

Is adding oral ondansetron to pre-medication regimen of unsedated EGD safe, easy to conduct, and well-accepted by patients? May taking ondansetron prior to EGD reduce the discomfort of patients during the endoscopic process? May taking ondansetron prior to EGD reduce the intensity of patient gagging and nausea, and the incidence of vomiting ? Researchers will compare premedication of oral ondasetron and topical pharyngeal anesthesia (dyclonine hydrochloride mucilage) with topical pharyngeal anesthesia only to answer the questions above.

Participants will be treated with one of the following regimens according to the randomization result:

• Oral ondansetron of 8 mg 2 hours prior to endoscopic process and dyclonine hydrochloride mucilage to be gurgled 15 minutes prior to endoscopic process;
• dyclonine hydrochloride mucilage to be gurgled 15 minutes prior to endoscopic process.

After the endoscopic process is finished, patients will be asked to fill in a questionnaire that contains the following items, all measured by NRS 0-10:

• Overall discomfort;
• Intensity of gagging;
• Willingness to undergo unsedated EGD again if indicated.

Study Overview

• Status: Active, not recruiting
• Conditions: Esophagogastroduodensocopy (EGD) Procedure
• Intervention / Treatment: Drug: ondansetron and dyclonine hydrochloride; Drug: dyclonine hydrochloride only

• Study Type: Interventional
• Enrollment (Actual): 40
• Phase: Phase 4

Contacts and Locations

Study Locations

• China
  • Beijing Municipality
    • Beijing, Beijing Municipality, China, 100730
      • Peking Union Medical College Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• patients scheduled for follow-up EGD at PUMCH
• Signing a written informed consent.

Exclusion Criteria:

• Contraindications for esophagogastroduodenoscopy.
• History of upper gastrointestinal tract surgery.
• With conditions indicated for emergency EGD, such as upper gastrointestinal bleeding
• Severe diseases of the heart, kidney, respiratory system, central nervous system, and hematopoietic system.
• Pregnancy.
• Neuropsychiatric disorders, severe depression and severe anxiety.
• Allergy to ondansetron or dyclonine hydrochloride.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Supportive Care
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: oral ondansetron and dyclonine hydrochloride mucilage	Drug: ondansetron and dyclonine hydrochloride; Patients will take 8 mg oral ondansetron 2 hours prior to EGD process in addition to dyclonine hydrochloride mucilage to be gurgled 15 minutes prior to EGD process.
Other: dyclonine hydrochloride mucilage only	Drug: dyclonine hydrochloride only; Patients will be instructed to gurgle 10 mL of dyclonine chloride mucilage (0.01 g/mL) and gurgle for 1 minute 15 minutes prior to endoscopic process.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in overall discomfort	All 20 patients were follow-up patients who had unsedated EGD before. They assessed their degree of overall discomfort during the curent examination and the previous examination, both in numeric rating scale (NRS, on a scale from 0 to 10, 0 means no discomfort, 10 means extremely uncomfortable). Change in overall discomfort is the value of the difference between the previous and current NRS (previous-current).	from the previous endoscopy to 30 minutes after the current endoscopy is finished

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Intensity of patient gagging evaluated by endoscopist	measured by NRS 0-10, (0 none, 10 extremely strong) in a questionnaire given to endoscopists after the endoscopic process is finished	from the start of the endoscopic process to the end of the endoscopic process
Patient willingness to undergo unsedated EGD again	the willingness of patients to undergo unsedated EGD in the same method again, assessed by NRS 0-10 (0, not willing at all; 10 completely willing).	from start of endoscopy to 30 minutes after the examination is finished
Endoscopist satisfaction for patient cooperation	satisfaction of endoscopist for patient cooperation in this process, assessed by NRS 0-10 (0, not satisfied at all; 10 very satisfied).	from the start to the end of the endoscopic process
Change in patient gagging intensity	Patients assessed their gagging intensity during the curent examination and the previous examination, both in NRS 0-10, 0 means no gagging, 10 means extremely intense gagging. Change in overall discomfort is the value of the difference between the previous and current NRS (previous-current).	from the previous endoscopic examination to 30 minutes after the current examination is finished.

Collaborators and Investigators

• Sponsor: Peking Union Medical College Hospital

Study record dates

Study Major Dates

• Study Start (Actual): July 1, 2025
• Primary Completion (Actual): September 28, 2025
• Study Completion (Estimated): June 10, 2026

Study Registration Dates

• First Submitted: November 23, 2025
• First Submitted That Met QC Criteria: November 23, 2025
• First Posted (Actual): December 4, 2025

Study Record Updates

• Last Update Posted (Actual): May 1, 2026
• Last Update Submitted That Met QC Criteria: April 27, 2026
• Last Verified: April 1, 2026

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Heterocyclic Compounds, 1-Ring; Heterocyclic Compounds; Heterocyclic Compounds, 2-Ring; Heterocyclic Compounds, Fused-Ring; Azoles; Imidazoles; Indoles; Heterocyclic Compounds, 3-Ring; Carbazoles; Ondansetron; dyclonine
• Other Study ID Numbers: ON-COMFORT25

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: No
• Studies a U.S. FDA-regulated device product: No