2 Answers

I know what it is, b/c I had that problem. For years, my left eye kept watering, and it was embarrasing. I  went to several optomitrists about it and 3 optholmologists about it. One of them gave me the straight answer........that it is a blocked tear duct, So he had me go into the out-patient surgery dept and another Dr. frined of his  cleaned out my tear duct, with a small wire; and he made an opening in the inner corner of my lower eyelid to allow for the tears to go into the lower lid ===then down into my nose. They put me in lah lah land before they did it. And gave me a local anesthetic

The tearing is caused by the dryness in your eye.  You can try artificial tears, like Blink, Optive (which lasts longer), or Systane which are obtainable over the counter.  Consult a pharmacist in a drug store for a better one.