GEL & MEDication Dysphagia (GELMED)

Influence of Swallow Gel and Semi-solid Consistency on Medication Dysphagia: A Multicenter Observational Study

This research project examines the prevalence of medication-related dysphagia in patients with dysphagia-associated diseases. Its primary aim is to assess how frequently swallowing difficulties occur during medication intake and to evaluate the impact of different consistencies-such as semi-solid formulations and commercial swallowing gels-on the swallowing process. Flexible endoscopic evaluation of swallowing serves as the diagnostic gold standard to determine whether alternative administration forms can facilitate safer swallowing. The findings are intended to support the optimization of medication intake and the prevention of complications in patients with dysphagia.

Study Overview

• Status: Recruiting
• Conditions: Healthy Participants; Neurological Diseases or Conditions
• Intervention / Treatment: Other: medication swallowing

Detailed Description

Dysphagia refers to an impairment of the swallowing process, encompassing the transport of the food bolus from the oral cavity to the gastrointestinal tract. In neurological patients, combined disturbances of the oral and pharyngeal phases frequently occur, known as oropharyngeal dysphagia. This form of dysphagia not only significantly reduces quality of life but may also lead to severe complications.

A particularly relevant aspect of dysphagia is impaired swallowing of medication, referred to as medication dysphagia. This may compromise swallowing efficiency, for example when tablets or capsules remain in the oral cavity or pharynx and dissolve prematurely. Swallowing safety can also be affected, especially in cases of penetration or aspiration during medication intake.

To compensate for these difficulties, patients are often advised to swallow medication together with semi-solid substances instead of liquids. In addition, a commercially available swallowing gel has recently become accessible, designed specifically to facilitate medication intake in patients with dysphagia.

Despite its clinical relevance, medication dysphagia has rarely been investigated systematically with instrumental diagnostics. In particular, the compensatory strategies widely applied in practice have not yet been scientifically evaluated.

Objectives

This research project aims to determine the prevalence of medication dysphagia in patients with dysphagia-associated diseases and to assess the effects of different consistencies on the swallowing process. Specifically, the study will address the following questions:

What is the prevalence of medication dysphagia across different underlying diseases?

Is there an association between medication dysphagia and dysphagia for food and liquids?

How does the addition of a semi-solid vehicle affect the efficiency of medication swallowing?

How does the addition of a semi-solid vehicle affect the safety of medication swallowing?

How does the addition of a semi-solid vehicle influence subjective swallowing difficulties and swallowing-related anxiety during medication intake?

How does the use of a swallowing gel affect the efficiency of medication swallowing?

How does the use of a swallowing gel affect the safety of medication swallowing?

How does the use of a swallowing gel influence subjective swallowing difficulties and swallowing-related anxiety during medication intake?

Study Protocol

This is a prospective, multicenter interventional study. Eligible participants include patients with diseases associated with dysphagia who are scheduled for a clinically indicated Flexible Endoscopic Evaluation of Swallowing (FEES). Healthy control subjects will also be recruited for comparison.

At the University Hospital Düsseldorf, patients with neurovascular, neurodegenerative, neuroinflammatory, or neuromuscular diseases will be included. Medication dysphagia will be assessed using FEES. Three experimental paradigms are planned:

Standard FEES with food and liquid:

In the following order: 10 cc green-colored jelly (semi-solid), 10 cc methylene-blue-dyed liquid, and a piece of white bread (~3 × 3 × 0.5 cm, solid).

Three swallows will be tested for each bolus.

FEES assessment of medication dysphagia:

Three swallow trials will be conducted in randomized order for each of the following conditions:

1. Placebo medication with methylene-blue-dyed water.
2. Placebo medication with a semi-solid vehicle.
3. Placebo medication with the swallowing gel GLOUP®.

Subjective evaluation:

Perceived swallowing difficulty and swallowing-related anxiety will be assessed for each condition using a numerical rating scale (1-10).

Analysis

Medication dysphagia will be evaluated using a previously published and validated FEES-based classification system developed by our research group. This tool enables systematic assessment of swallowing efficiency and safety during medication intake.

• Study Type: Observational
• Enrollment (Estimated): 500

Contacts and Locations

• Study Contact: Name: Bendix FEES Labeit, MD; Phone Number: 0049211 8117887; Email: Bendix.Labeit@med.uni-duesseldorf.de

Study Locations

• Germany
  • Onsabrück, Germany
    • Recruiting
    • Hospital Osnabrücl
    • Contact: Rainer Dziewas; Phone Number: 0049541 4050; Email: Rainer.Dziewas@klinikum-os.de
    • Contact: Email: Rainer.Dziewas@klinikum-os.de
  • North Rhine-Westphalia
    • Düsseldorf, North Rhine-Westphalia, Germany, 40225
      • Recruiting
      • University Hospital Düsseldorf
      • Contact: Bendix FEES Labeit, MD; Phone Number: 0049211 8117887; Email: Bendix.Labeit@med.uni-duesseldorf.de
    • Münster, North Rhine-Westphalia, Germany, 48149
      • Recruiting
      • University Hospital Münster
      • Contact: Sonja Suntrup-Krüger, MD; Phone Number: 0049251 8355555; Email: Sonja.Suntrup-Krueger@ukmuenster.de
      • Contact: Email: Sonja.Suntrup-Krueger@ukmuenster.de

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: Yes

• Sampling Method: Non-Probability Sample

Study Population

Patients and relatives of the participating clinics

Description

Inclusion Criteria:

Patients:

Adults with a dysphagia-associated disease (neurovascular, neurodegenerative, neuroinflammatory, or neuromuscular disorders; in other centers also ENT-related diseases), for whom FEES is clinically indicated.

Capable of providing informed consent and cognitively able to follow the study protocol.

Healthy Controls Adults without any dysphagia-associated disease (no neurovascular, neurodegenerative, neuroinflammatory, or neuromuscular disorders; no ENT-related diseases with structural abnormalities of the oropharynx or esophagus).

Capable of providing informed consent and cognitively able to follow the study protocol.

Exclusion Criteria:

No additional exclusion criteria beyond those specified in the inclusion criteria.

Study Plan

How is the study designed?

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
neurogenic dysphagia group; patients with neurological diseases that may lead to dysphagia	Other: medication swallowing; Three swallow trials will be conducted in randomized order for each of the following conditions: Placebo medication with methylene-blue-dyed water.; Placebo medication with a semi-solid vehicle.; Placebo medication with the swallowing gel GLOUP®.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Medication dysphagia score according to Labeit et al 2022; DOI: 10.1038/s41531-022-00421-9		on the day of enrollment. This is not a longitudinal study but a one-time examination; all assessments take place on the day of enrollment.
Medication dysphagia swallowing score according to FEES (Labeit et al 2022; doi: 10.1038/s41531-022-00421-9)	as published here: Labeit et al 2022; doi: 10.1038/s41531-022-00421-9	on the day of enrollment. This is not a longitudinal study but a one-time examination; all assessments take place on the day of enrollment.

Collaborators and Investigators

• Sponsor: Heinrich-Heine University, Duesseldorf

Study record dates

Study Major Dates

• Study Start (Actual): September 15, 2025
• Primary Completion (Estimated): September 15, 2027
• Study Completion (Estimated): September 15, 2027

Study Registration Dates

• First Submitted: September 15, 2025
• First Submitted That Met QC Criteria: November 26, 2025
• First Posted (Actual): November 28, 2025

Study Record Updates

• Last Update Posted (Actual): November 28, 2025
• Last Update Submitted That Met QC Criteria: November 26, 2025
• Last Verified: September 1, 2025

More Information

Terms related to this study

• Other Study ID Numbers: 2024-2989

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: demographic data, clinical description of the cohort and swallowing results
• IPD Sharing Time Frame: beginning of recruitment until end of study
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL; SAP; ICF; ANALYTIC_CODE

Drug and device information, study documents

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