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

Research reveals biological mechanism of a leading cause of childhood blindness

November 16, 2017
Scientists at the Virginia Tech Carilion Research Institute (VTCRI) have revealed the pathology of cells and structures stricken by optic nerve hypoplasia, a leading cause of childhood blindness in developed nations.

Genetic treatment for blindness may soon be reality

November 11, 2017
Patients who had lost their sight to an inherited retinal disease could see well enough to navigate a maze after being treated with a new gene therapy, according to research presented today at AAO 2017, the 121st Annual Meeting ...

Study finds donor corneas can be safely preserved for longer period

November 10, 2017
Results from a large, national clinical trial show that corneal donor tissue can be safely stored for 11 days without negatively impacting the success of transplantation surgery to restore vision in people with diseases of ...

Exploring the genetics of glaucoma and retinal development

November 10, 2017
Guillermo Oliver, PhD, the Thomas D. Spies Professor of Lymphatic Metabolism, recently published two studies related to the eye, one on retinal formation and the other on the genetics behind glaucoma.

Scientists discover potential treatment to stop glaucoma in its tracks

November 6, 2017
Vision scientists at the University of California, Berkeley, and the University of Toronto have discovered that naturally occurring molecules known as lipid mediators have the potential to halt the progression of glaucoma, ...

New focus on correcting refractive vision

October 25, 2017
While doctors take delight in solving the common issue of refractive vision error by prescribing eye glasses, Flinders University researchers have found that many patients are upset with this solution and claim it affects ...

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.