What Causes a Watery Eye?

In the past couple months, I've had a weeping eye. My eyelashes often feel damp, and a tear will occasionally run down from the corner of my watery eye. It isn't painful, but my teary eye can be embarrassing since people sometimes think I'm upset and crying. Still, the watery eye caused me concern, so I did what everyone does when they first suffer from an ailment - turned to the internet.

Yes, we all know we should go to the doctor, but it is tough to resist the immediacy of information online even when we know it will turn up some obscure deadly disease that scares the pants off us and which we probably don't have. I was surprised to find it difficult to find information about watery eyes (aside from weepy eyes in cats or dogs) and did eventually go to the doctor for evaluation. If you have a constant watery eye or even an occasionally weepy eye, you might be wondering yourself what caused it.

Allergies and Illness

According to the National Institutes of Health, allergies and the common cold are common causes of watery eyes. This is likely caused by your body trying to get rid of any allergens in your eye in the case of allergies, and because of a partially or fully blocked tear duct in the event of a cold. Our tear ducts drain through a tube into our noses, so when we are stuffy, it can cause blockage or irritation of that tube, which makes it more difficult for tears to drain as quickly as they normally do. As it turns out, a very bad cold which then turned into a very bad sinus infection was the cause of my watery eye.

Infections

Anyone who has been in an elementary school classroom is familiar with pink eye (conjunctivitis) and knows it can cause not only weepy eyes, but also pinkness of the eye or eyelid, yellow discharge and crusting around the eye. It's pretty hard to mistake it for anything else, but did you know weepy eyes can also be caused by a herpes virus? And, just like genital herpes or oral herpes (cold sores), once you have it you are much more likely to have a flare up in the future. Bacterial infections can also give you watery eyes. Luckily, there are several medications available to treat weepy eyes caused by infection.

Tumors

Yes, tumors in your tear duct can cause watery eyes. No, your teary eye probably isn't caused by a tumor. According to the National Cancer Institute, your odds of the weepy eye being caused by a tumor (known as an intraocular melanoma) is 4.3 per million - or .00043%. So put down the phone, no need to call your best friend to tell him you think you have an eye tumor.

There are other causes of watery eyes, but these are the most common or most interesting ones. Now that you've played armchair physician, pick up the phone, call your doctor for an appointment, and find out the real cause behind your weepy eye.

Sources:
National Institutes of Health, http://www.nih.gov/
National Cancer Institute, Intraocular (Eye) Melanoma Treatment, http://www.cancer.gov/cancertopics/pdq/treatment/intraocularmelanoma/HealthProfessional/page2/print