Topical Menthol For Tear Secretion

NCT07109609 | Enrolling By Invitation Phase 2 DMC

• 1 other identifier: M240706
• Study Type: interventional
• Target: 30
• Locations: 1 country
• Sites: 1

Brief Summary

Tears are the natural way to keep eyes moist, and tears are important for good vision and healthy eyes. Eyes without enought tears get dry and sore. The natural and normal way to stimulate secretion of tears is by turning on cold sensors that are located on the cornea of the eye. Tear are normally released across the eyeball in a finely balanced system that balances out that natural evaporation. But sometimes there is not enough tear secretion to balance out the evaporation of tears and eyes can get sore. The aim here is to test whether menthol in its vapor form may possibly turn on those cold sensors and thus cause secretion of tears. Use of menthol vapors may be like having a switch to release more tears. The aim of this clinical trial is to test the hypothesis that a menthol solution applied onto a cheek will release enough menthol vapor into the air flowing up over the eye's cornea to stimulate cold sensors enough to make a tear flow from the eye. If the hypothesis that menthol safely stimulates tear secretion in healthy people proves to be correct, then this clinical trial may inspire more new research into the use of menthol as an alternative to the use of eye drops for some people.

Conditions

Healthy; Dry Eyes

Keywords

tear secretion; dry eyes; eye drops; menthol; vapor; cornea

Outcome Measures

Primary Outcomes (4)

• Objective measure of tear stimulation Yes or No

  The outcome is the binary yes/no observation of active tear secretion that overflows to the skin below the bottom eyelashes. Subject sits in still air while wearing glasses to ensure correct positioning of the topical application. The solution of menthol or placebo is dispensed from a roller-ball bottle to the right eye only, onto an area about 2cm x 2 cm just below the bottom rim of the glasses; that is, inferior to the pupil, and in line with the bottom of the nose. Within 5 minutes of sitting in still air, If moisture is evident below the bottom eyelashes, glasses are removed and tissue is dabbed, or wiped under bottom eyelash to take up the tear. If that wipe increases the weight of the tissue by at least 6 milligrams, then a "Yes" response is recorded. If after 5 minutes a wipe of tissue across the bottom eyelashes of the right eye does not increase the weight of tissue by at least 6 milligrams, a "No" is recorded to indicate that there was no increase in tear secretion.

  Participant is observed for 5 minutes after application, to record tear-weight data, and the related questions that are asked are completed within 10 minutes after applicaiton.

• Weight of tear

  The actual measured weight of the tear(s) collected onto the tissue, from below the right eye.

  Measured at 5 minutes after dose application.

• Was there a subjective difference between left and right eyes in terms of sense if moisture

  Response to the question: " Which eye feels more moist? Left eye more moist or No difference (both same) or ….Right eye more moist"

  5 to 10 minutes after application

• Weight of nasal secretion blown into tissue.

  The purpose is to test whether there is evidence of shared innervation of TRPM8 receptors (the menthol-responsive sensors for cold) in cornea and nasal subepithelium. The particpant holds closed the left nostril, while blowing into a tissue from the right nostril. The increase in weight of tissue is measured.

  Within 10 minutes of applying the dose.

Secondary Outcomes (4)

• Weight of nasal secretion

  5 to 10 minutes after application

• Discomfortable feeling at the treated eye.

  10 minutes

• Degree of cooling or pain at the skin where the dose was applied.

  10 minutes

• Did the procedure increase sense of runny nose?

  10 minutes

Study Arms (2)

Topical Menthol in Oil

EXPERIMENTAL

Menthol solution rolled onto the cheek below rim of a pair of glasses

Drug: Topical application of 20% menthol solution in MCT oil.

Topical Placebo Oil only

PLACEBO COMPARATOR

Oil vehicle only rolled onto the cheek below rim of a pair of glasses

Drug: Topical Placebo Oil rolled onto the cheek.

Interventions

Topical application of 20% menthol solution in MCT oil. DRUG

To facilitate reproducible and correct application of the solution, the subject wears glasses while the product is applied. The solution is rolled onto one cheek by rolling it to an area of about 2cm X 2cm at the cheekbone, underneath the bottom rim of the glasses worn. This method delivers about 12 mg solution, i.e. 2.4 mg menthol to one cheek. Or this method delviers 12 mg of placebo oil. The subject then sits in still air for 5 minutes, at which point tissue is wiped across the skin below the bottom eyelashes to permit the weighing of secreted tear.

Topical Menthol in Oil

Topical Placebo Oil rolled onto the cheek. DRUG

To facilitate reproducible and correct application of the Placebo oil, the subject wears glasses while the product is applied. The Placebo oil is rolled onto one cheek by rolling it to an area of about 2cm X 2cm at the cheekbone, underneath the bottom rim of the glasses worn. This method delivers zero active agent. The subject then sits in still air for 5 minutes, at which point tissue is wiped across the skin below the bottom eyelashes to permit the weighing of secreted tear.

Topical Placebo Oil only

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Not under care of an opthalmologist for treatment of dry-eyes

You may not qualify if:

• Excluded if "Yes" to any of the questions below.
• Are you allergic to menthol or to menthol-containing products like tooth paste or certain cold remedies?
• Are you wearing contact lenses during the time of testing? \_\_\_\_\_\_\_\_
• Are there tears present prior to applying the menthol? \_\_\_\_\_\_\_\_
• Did you use of eye drops during the hour before participation? \_\_\_\_\_\_\_\_
• Do you have broken, irritated, sensitive skin and/or acne at or around application site? \_\_\_\_\_\_\_\_
• Do you have a history of atopy, allergic diseases at the skin of your cheeks?
• Do you have Stevens-Johnson syndrome, which is any known skin response to chemical, thermal, or radiation injury to the application area? \_\_\_\_

Sponsors & Collaborators

• Reinhold Vieth: lead
• Stearacl Inc: collaborator

Study Sites (1)

Stearacl Incorporated.

Toronto, Ontario, M4K1X4, Canada

Location

MeSH Terms

Conditions

Dry Eye Syndromes; Corneal Diseases

Condition Hierarchy (Ancestors)

Lacrimal Apparatus Diseases; Eye Diseases

Study Design

• Study Type: interventional
• Phase: phase 2
• Allocation: RANDOMIZED
• Masking: QUADRUPLE
• Who Masked: PARTICIPANT, CARE PROVIDER, INVESTIGATOR, OUTCOMES ASSESSOR
• Purpose: BASIC SCIENCE
• Intervention Model: PARALLEL
• Sponsor Type: INDUSTRY
• Responsible Party: SPONSOR INVESTIGATOR
• PI Title: CEO Stearacl Inc, Canada

Study Record Dates

• First Submitted: July 30, 2025
• First Posted: August 7, 2025
• Study Start: August 17, 2025
• Primary Completion: November 7, 2025
• Study Completion: December 1, 2025
• Last Updated: September 16, 2025

Record last verified: 2025-07

Data Sharing

• IPD Sharing: Will share
• Shared Documents: STUDY PROTOCOL, SAP, ICF, CSR
• Time Frame: 1 month after final publication
• Access Criteria: The senior author of any ensuing publication will correspond with suitably qualified investigators, to discuss the type and form of data made available.

Locations

CA (1)