Dry eye disease is no laughing matter — or is it?

More than 360 million people around the world suffer from chronically red, scratchy or irritated eyes, a condition that can worsen with stress. Researchers in China and the UK believe they may have found an unusual solution that doesn’t involve eye drops — laughter.

“As a safe, environmentally friendly, and low-cost intervention, laughter exercise could serve as a first-line, home-based treatment for people with symptomatic dry eye disease,” said the authors of a study published Wednesday in the BMJ.

The researchers were inspired by evidence suggesting that laughter therapy relieves depression, anxiety and chronic pain while strengthening the immune system. Laughter has been shown to decrease stress hormones, activate immune cells and increase infection-fighting antibodies.

For this study, 283 dry eye disease sufferers were randomly assigned laughter exercise or 0.1% sodium hyaluronic acid eye drops.

The laughter exercise group was tasked with watching an instructional video and repeating the phrases “Hee hee hee, hah hah hah, cheese cheese cheese, cheek cheek cheek, hah hah hah hah hah hah” 30 times in five minutes four times a day. They used an app to enhance their facial movements.

Meanwhile, the other group applied 0.1% sodium hyaluronic acid eye drops to both eyes four times a day, tracking the process with the same app. 

Both treatments stopped at eight weeks — researchers noted changes in eye discomfort at the 10- and 12-week marks.

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They determined that laughter exercise seemed as effective as eye drops and more beneficial for certain eye functions and the participant’s mental health.

“Laughter exercise might alleviate dry eye disease indirectly by creating a persisting positive effect on lifestyle,” the researchers wrote in their findings.

There were some limitations to the study, including possible bias because the participants knew the treatment they received. Plus, laughter exercise takes more time than eye drop application.

The researchers say future studies should assess how long and how often laughter exercises should be done for maximum success.

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Dr. Matthew Gorski, a Northwell Health ophthalmologist, called the study findings “interesting,” but said they shouldn’t be taken at face value.

“Laughter exercises certainly would be an innovative and fun way to treat dry eye syndrome,” Gorski, who was not involved in the research, told The Post. “Definitive conclusions and recommendations to patients shouldn’t necessarily be made based on these results. Additional research studies are necessary to confirm the results.”