Caffeine use may offer relief for millions of dry eye sufferers

April 17, 2012

Researchers at the University of Tokyo's School of Medicine have shown for the first time that caffeine intake can significantly increase the eye's ability to produce tears, a finding that could improve treatment of dry eye syndrome. This common eye condition affects about four million people age 50 and older in the United States. For many, dry eye syndrome is simply uncomfortable and annoying, but for others it escalates into a vision-threatening disease. All of the 78 participants in the new study produced significantly more tears after consuming caffeine than after taking a placebo. The study is available in Ophthalmology, the journal of the American Academy of Ophthalmology.

Dry eye syndrome involves malfunction of the rate of tear production, the quality of tears, and/or the rate of evaporate from the surface of the eye. Anyone can experience dry eye, though it is more common among women. Symptoms can include gritty, scratchy or burning sensations, excessive tearing, and/or production of stringy .

The research team, by Reiko Arita, MD, PhD, was motivated by an earlier study that had shown a reduced risk for dry eye in caffeine users: 13 percent of users had the syndrome compared with nearly 17 percent of non-users. The team knew that caffeine was likely to stimulate tear glands, since it is known to increase other , such as saliva and . They also knew that people respond differently to caffeine, so they analyzed study participants' for two genetic variations that play important roles in caffeine metabolism. Tear production proved to be higher in study subjects who had the two genetic variations.

"If confirmed by other studies, our findings on caffeine should be useful in treating dry eye syndrome," said Dr. Arita. "At this point, though, we would advise using it selectively for patients who are most sensitive to caffeine's stimulating effects."

The study subjects were divided into two groups: one received caffeine tablets in the first session and a placebo in the second session, while the order was reversed for the other group. Tear volume was measured within 45 minutes of consuming the tablets. All sessions took place between 10 a.m. and noon, a time of day when tear production is usually stable. No subjects knew whether they received caffeine or the placebo. All abstained from caffeine use for six days prior to each session and used no drugs during the sessions. To be eligible for the study subjects had to be free of high blood pressure, dry eye syndrome, allergies that affect the eye, glaucoma, and other eye diseases and conditions that can interfere with tear production. The study also found that tear drainage rates were not affected by caffeine.

Dry eye can be very uncomfortable and interfere with vision. It's important to see an ophthalmologist if symptoms continue, since advanced cases can cause eye damage and permanent vision problems. Current treatment options range from simple warm compresses, eye washes and artificial tears to medications and tear drainage devices.

Explore further: Scientists 'see' the early cellular cause of dry eye disease for the first time

Related Stories

Scientists 'see' the early cellular cause of dry eye disease for the first time

May 31, 2011
If you are one of the millions of people around the world who struggle with dry eye disease, good news is on the way. A new research discovery published in the Journal of Leukocyte Biology offers hope for new drugs that treat ...

Can consuming caffeine while breastfeeding harm your baby?

February 21, 2012
Babies are not able to metabolize or excrete caffeine very well, so a breastfeeding mother's consumption of caffeine may lead to caffeine accumulation and symptoms such as wakefulness and irritability, according to an interview ...

Recommended for you

Combination of type 2 diabetes and sleep apnoea indicates eyesight loss within four years

July 4, 2017
Research led by the University of Birmingham has discovered that patients who suffer from both Type 2 diabetes and obstructive sleep apnoea are at greater risk of developing a condition that leads to blindness within an average ...

Nearly 60% of pinkeye patients receive antibiotic eye drops, but they're seldom necessary

June 28, 2017
A new study suggests that most people with acute conjunctivitis, or pinkeye, are getting the wrong treatment.

Magnetic implants used to treat 'dancing eyes'

June 26, 2017
A research team has successfully used magnets implanted behind a person's eyes to treat nystagmus, a condition characterised by involuntary eye movements.

Drug shows promise against vision-robbing disease in seniors

June 21, 2017
An experimental drug is showing promise against an untreatable eye disease that blinds older adults—and intriguingly, it seems to work in patients who carry a particular gene flaw that fuels the damage to their vision.

Reproducing a retinal disease on a chip

June 15, 2017
Approximately 80% of all sensory input is received via the eyes, so suffering from chronic retinal diseases that lead to blindness causes a significant decrease in the quality of life (QOL). And because retinal diseases are ...

New gene therapy for vision loss proven safe in humans

May 16, 2017
In a small and preliminary clinical trial, Johns Hopkins researchers and their collaborators have shown that an experimental gene therapy that uses viruses to introduce a therapeutic gene into the eye is safe and that it ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.