Dyclonine vs. Tetracaine for Local Anesthesia in Unsedated Gastroscopy

Dyclonine Hydrochloride Mucilage Versus Tetracaine Hydrochloride Jelly for Local Anesthesia in Unsedated Gastroscopy: A Non-inferiority Randomized Controlled Trial

Gastroscopy is a key diagnostic approach for upper gastrointestinal diseases, but pharyngeal passage of the gastroscopy often causes participants' discomfort. Topical pharyngeal anesthetics are routinely used to alleviate such discomfort. Dyclonine hydrochloride mucilage and tetracaine hydrochloride jelly are the two most commonly used topical pharyngeal anesthetics in clinical practice. Although both agents are widely used, their comparative efficacy in unsedated gastroscopy remains unclear, and high-quality evidence is scarce. This study aims to compare their anesthetic efficacy,participant comfort, and safety.

Study Overview

• Status: Not yet recruiting
• Conditions: Gastrointestinal Symptoms
• Intervention / Treatment: Drug: Dyclonine hydrochloride mucilage; Drug: Tetracaine Hydrochloride Jelly

Detailed Description

A total of 208 participants undergoing unsedated gastroscopy will be enrolled and randomly assigned in a 1:1 ratio to either the dyclonine group or the tetracaine group. Participants in the dyclonine group will receive dyclonine hydrochloride mucilage for pharyngeal topical anesthesia, whereas those in the tetracaine group will receive tetracaine hydrochloride jelly. The primary outcome is participant comfort assessed using the Visual Analogue Scale (VAS, range 0-10) during the gastroscopy. Secondary outcomes include antifoaming efficacy, the incidence of nausea and vomiting, the duration of gastroscopy, participant and endoscopist satisfaction, and the incidence of adverse events.

• Study Type: Interventional
• Enrollment (Estimated): 208
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Xingshun Qi; Phone Number: 18909881019; Email: xingshunqi@126.com
• Study Contact Backup: Name: Haoran Jia; Phone Number: 13730977073; Email: 2976851089@qq.com

Study Locations

• China
  • Liaoning
    • Shenyang, Liaoning, China
      • Department of Gastroenterology,General Hospital of Northern Theater Command
      • Contact: Xingshun Qi; Phone Number: 18909881019; Email: xingshunqi@126.com

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

• Age 18-75 years, of either sex;
• Scheduled for an unsedated gastroscopy;
• American Society of Anesthesiologists (ASA) physical status class I or II;
• Able to understand and cooperate with Visual Analogue Scale (VAS) comfort assessment;
• Willing to provide written informed consent voluntarily.

Exclusion Criteria:

• Known allergy to the study agents;
• Severe cardiopulmonary disease or hepatic/renal insufficiency;
• Long-term use of sedatives or analgesics, or history of alcohol abuse;
• Pregnancy or lactation;
• Dysphagia or trismus (limited mouth opening);
• Contraindications to upper gastrointestinal endoscopy, including acute perforation and active massive bleeding;
• Mental or cognitive disorders that may preclude cooperation with the procedure;
• Scheduled for therapeutic endoscopic procedures with an anticipated procedure time exceeding 15 minutes;
• Altered upper gastrointestinal anatomy due to prior total gastrectomy, esophagectomy, or subtotal gastrectomy.

Study Plan

How is the study designed?

Design Details

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

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Dyclonine Group	Drug: Dyclonine hydrochloride mucilage; Dyclonine hydrochloride mucilage (10 ml: 0.1 g) will be used. Each participant will hold 10 ml of the solution in the throat for 2 minutes before swallowing, 10-15 minutes prior to gastroscopy.
Active Comparator: Tetracaine Group	Drug: Tetracaine Hydrochloride Jelly; Tetracaine hydrochloride jelly (specification: 10 g : 0.1 g) will be administered 10-15 minutes prior to gastroscopy. A nurse will spray the jelly onto the root of the participant's tongue and then instruct the participant to swallow it.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Visual Analogue Scale(VAS) Score	Using a 0-10 Visual Analogue Scale (VAS), ranging from 0 (no discomfort) to 10 (worst possible discomfort), higher scores indicate worse outcome.	Within 5 minutes after completion of gastroscopy

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Patient-reported palatability acceptability	Palatability acceptability was rated on a 3-level scale ( good, moderate, poor).	Within 1-2 minutes of buccal or spray administration
Incidence of nausea and vomiting		Throughout the procedure and within 30 minutes after completion of gastroscopy
First-pass success rate		Throughout the intubation process
Antifoaming efficacy	Assessed by the endoscopist using a 4-point grading scale: no bubbles or foam, view is clear; few bubbles present, but without interfering with mucosal evaluation; moderate amount of bubbles and foam, causing some difficulty in evaluation; abundant foam and bubbles, making mucosal evaluation hardly possible.	Time of gastroscopy insertion into the gastric body
Duration of gastroscopy		Procedure time from endoscope insertion to withdrawal
Satisfaction of participant and endoscopist	Satisfaction is assessed using a 5-point Likert scale, ranging from very dissatisfied to very satisfied.	Within 5 minutes after completion of gastroscopy
Willingness to repeat gastroscopy (yes/no)		Within 5 minutes after completion of gastroscopy
Procedure-related pain score (VAS, 0-10)	Using a 0-10 Visual Analogue Scale (VAS), ranging from 0 (no pain) to 10 (worst possible pain), higher scores indicate more severe pain.	Throughout the entire gastroscopy procedure
Pharyngeal numbness after gastroscopy		Within 5 minutes after completion of gastroscopy
Swallowing function (assessed by salivary swallowing difficulty) after gastroscopy	Assessed by a 4-point grading scale: normal swallowing, no difficulty; mild difficulty, foreign body sensation but does not affect swallowing; moderate difficulty, obvious effort or mild choking; severe difficulty, unable to swallow saliva normally.	Within 5 minutes after completion of gastroscopy
Incidence of adverse events	Incidence of dizziness, headache, choking/coughing.	Throughout the procedure and within 30 minutes after completion of gastroscopy

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Pre-procedural anxiety assessed by the Amsterdam Preoperative Anxiety and Information Scale (APAIS).	Items are scored on a 5-point Likert scale (1 = not at all to 5 = extremely). The anxiety subscale consists of four items related to worry about the anesthetic and the procedure, with total scores ranging from 4 to 20. Higher scores indicate higher anxiety levels.	30 minutes prior to gastroscopy

Collaborators and Investigators

• Sponsor: General Hospital of Shenyang Military Region

Publications and helpful links

General Publications

• Abraham NS, Fallone CA, Mayrand S, Huang J, Wieczorek P, Barkun AN. Sedation versus no sedation in the performance of diagnostic upper gastrointestinal endoscopy: a Canadian randomized controlled cost-outcome study. Am J Gastroenterol. 2004 Sep;99(9):1692-9. doi: 10.1111/j.1572-0241.2004.40157.x.
• Wang L, Wen QH, Wen LJ, Qin JM, Ren CM, Wen LM. Disturbance of consciousness caused by dyclonine hydrochloride mucilage: a case report. BMC Anesthesiol. 2024 Jan 22;24(1):34. doi: 10.1186/s12871-024-02407-x.
• Han C, Li P, Guo Z, Guo Y, Sun L, Chen G, Qiu X, Mi W, Zhang C, Berra L. Improving mucosal anesthesia for awake endotracheal intubation with a novel method: a prospective, assessor-blinded, randomized controlled trial. BMC Anesthesiol. 2020 Dec 14;20(1):301. doi: 10.1186/s12871-020-01210-8.
• Jichao S, Cuida M, Mingxing C, Yunyun W, Dongdong Z. Oral dyclonine hydrochloride mucilage versus tetracaine spray in electronic flexible laryngoscopy: A prospective, randomized controlled trial. Am J Otolaryngol. 2016 Mar-Apr;37(2):169-71. doi: 10.1016/j.amjoto.2015.12.005. Epub 2015 Dec 9.

Study record dates

Study Major Dates

• Study Start (Estimated): July 1, 2026
• Primary Completion (Estimated): July 1, 2028
• Study Completion (Estimated): July 1, 2028

Study Registration Dates

• First Submitted: June 26, 2026
• First Submitted That Met QC Criteria: July 2, 2026
• First Posted (Actual): July 8, 2026

Study Record Updates

• Last Update Posted (Actual): July 8, 2026
• Last Update Submitted That Met QC Criteria: July 2, 2026
• Last Verified: June 1, 2026

More Information

Terms related to this study

• Keywords: Gastroscopy; Visual Analogue Scale; Topical Anesthesia; Non-inferiority Trial; Dyclonine Hydrochloride; Tetracaine Hydrochloride
• Other Study ID Numbers: XHNKKY-DTRCT

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