Watery eyes are sometimes accompanied by vision loss, and an individual should seek medical treatment when this is the case, according to Healthline. Most cases of watery eyes are temporary and resolve on their own, but it can develop into a chronic problem.
Tears are created in glands beneath the upper eyelids, and their function is to wash debris, foreign objects and dust out of the eyes as well as keep them lubricated, according to Healthline. A common cause for watery eyes is dry eye syndrome, wherein tears don't contain an even amount of water, oils and salt. In this case, they fail to be effective as a lubricant. When too many tears overwhelm the tear ducts or they are blocked by dust, wind and other allergens, the irritation of dry eyes causes an overabundance of tear production, resulting in watery eyes.
Additional causes of watery eyes include eye strain, eyelid inflammation, ingrown eyelash, and cuts or scrapes on the eye, as Healthline indicates. Infections such as conjunctivitis as well as bright lights, smog and other environmental factors can potentially cause the condition. Treatments for conditions such as chemotherapy, radiation and some prescription medications may also trigger excessive tearing. If tearing persists or if there is discharge, bruising, tenderness or bleeding from the eye, an individual should seek medical treatment.