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.

This is a proof-of-principle clinical trial. It is a double-blind, placebo-controlled, randomized clinical trial. Participants are not being seen by a physician for eye disease, and there is a 50% probability that a participant will receive active treatment, or 50% probability that they will just receive the carrier oil with nothing in it (placebo).

Inclusion Criteria:

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

Exclusion Criteria:

• • 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? ____

A spreadsheet of anonymized IPD collected throughout the trial may be made upon inquiry with the corresponding author of any peer-reviewed publication ensuing from this work.

1 month after final publication

The senior author of any ensuing publication will correspond with suitably qualified investigators, to discuss the type and form of data made available.