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The effect of caffeine on tear secretion
Kwaku Antwi Osei1, Godwin Ovenseri-Ogbomo, Samuel Kyei
1*OD †OD, MPH ‡OD, MPhil Department of Optometry, University of Cape Coast, Cape Coast, Ghana (KAO, GO-O, SK, MN); and Department of Optometry, University of Benin, Benin City, Edo State, Nigeria (GO-O).
Orally ingested caffeine appears to stimulate tear secretion in healthy individuals. This study found increased tear production within 90 minutes of caffeine consumption.
Area of Science:
- Ophthalmology
- Pharmacology
Background:
- Caffeine is a widely consumed psychoactive substance with debated effects on tear film dynamics.
- Understanding caffeine's impact on ocular physiology is crucial for managing eye health.
Purpose of the Study:
- To investigate the effect of orally ingested caffeine on tear secretion in healthy volunteers.
- To determine if caffeine consumption influences tear production rates.
Main Methods:
- A placebo-controlled, crossover study involving 41 healthy volunteers (ages 20-26).
- Participants received either caffeine (5.0 mg/kg) or a placebo (water) in a randomized, masked manner.
- Schirmer 1 scores were measured at baseline and at 45, 90, 135, and 180 minutes post-treatment.
Main Results:
- Schirmer 1 scores showed a statistically significant increase at 45 and 90 minutes after caffeine intake (p < 0.05).
- No significant correlation was found between age, body mass, blood pressure, or gender and caffeine's effect on tear secretion.
- The study demonstrated a clear stimulatory effect of caffeine on tear production.
Conclusions:
- Orally ingested caffeine stimulates tear secretion in healthy subjects without dry eye.
- Caffeine may be a factor influencing ocular surface hydration.
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