Conditions: Dry Eye
Allocation: RANDOMIZED | Intervention model: CROSSOVER
Enrollment: 48
Healthy volunteers: yes

Brief summary:
The purpose of the study is to analyze the sensation to eye drops containing menthol in people with healthy eyes and in people with dry eyes. This study also examines the temperature of your eye using an Infrared Camera.

Detailed description:
Dry eye disease (DED) has been defined as a multifactorial disease of the tears and ocular surface that results in symptoms of discomfort, visual disturbance, and tear film instability with potential damage to the ocular surface. It is accompanied by increased osmolarity of the tear film and inflammation of the ocular surface1. An estimated 25 million Americans are reported to have dry eye disease (DED)2, which is a number that will only increase with the U.S. aging population3. The only treatment currently available in the U.S. targets inflammation on the ocular surface. Because dry eye is a complicated disease that encompasses many conditions of the eye, diversified ways to treating the disease are necessary. Some recent studies suggests that some Dry Eye symptoms are caused by corneal cold thermoreceptors (such as TRPM8) chronically firing at below-normal thresholds. It thus logically follows that dry eye patients could be distinguished from normal patients by possessing higher symptom responses secondary to topical application of menthol, a potent agonist of TRPM8. If dry eye patients indeed have lower threshold firing of TRPM8, agonizing TRPM8 with menthol will elicit a more severe symptom response, given equal concentrations across populations.

To fully elucidate this relationship between TRPM8 agonists, sensation, and tear film cooling, two dry eye populations will be tested - one population which has exhibited symptom response to a previous dry eye agent, and one population with no symptom response to the same agent.

Arms:
arm 1: Menthol containing over the counter eyedrop arm 2: Non-Menthol containing over the counter eyedrop

Interventions: intervention 1: Rohto (r) Hydra intervention 2: Systane (r) Ultra
Intervention descriptions: intervention 1: Rohto (r) Hydra; Over the counter Eyedrop, 1 gtt OU single-masked in-office dose intervention 2: Systane (r) Ultra; Over the counter Eyedrop, 1 gtt OU single-masked in-office dose

Protocol document: