Usually if one eye keeps watering there are any reasons for it. It can be trauma, it can be infection. Along infections it can be bacterial, viral and there are other infections inside the eye it can be glaucoma which can be in one eye. It can be uveitis which can also be in one eye. These are some of the common cause. Dryness of the eye can produce watering because the signal to the brain can only go that “ I am dry, give me water”. This signal goes to the brain. The brain cannot give mucus but can give water. So he will continuously give you water. So it will not be just water in one eye. It will go to the other eye, to the upper respiratory tract, nose, sinuses. These are all symptoms of dryness of the eye.
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