What causes you to have uncontrollable tears?

Foreign body in the eye:When a foreign object—such as dust or an eyelash—is lodged in the eye, the body produces more tears to flush it out. Additionally, things you can't see with the naked eye—like particles in smoke or chemicals in onions—can also trigger this reaction.

Dry eyes:This problem can occur when the body doesn't produce enough tears, due to the eyes drying out too quickly, or due to an imbalance of water, oil, and mucus. There are many causes for this condition. The body will react by producing more tears.

Conjunctivitis (pink eye):This is a common cause of watery eyes in both children and adults. The condition causes one or both eyes to become red, itchy, and feel as if there is sand in them. Bacteria or viruses are common causative agents.

Allergy:Watery, itchy eyes often accompany coughs, runny noses, and other allergy symptoms. You may also have an allergic eye condition. A cold can also cause watery eyes, but it doesn't usually cause itching. This is one way to differentiate between a cold and an allergy.

Blocked tear ducts:Normally, tears flow from the lacrimal glands above the eye, spilling onto the surface of the eyeball and draining into the glands at the corners of the eyes. But if these glands become blocked, tears will accumulate and keep your eyes watery. There are many causes for this, such as infection, injury, and even aging.

Scratched eye:Dust, sand, and contact lenses can scratch the cornea, causing redness, pain, tearing, and sensitivity to light. While these scratches usually heal on their own within two days, you should see a doctor to ensure there is no infection.

Squeeze:A stye can cause watery eyes and a small, painful, swollen lump at the edge of the eyelid. Bacteria cause styes, and they usually disappear on their own within a few days. It's best not to try to squeeze a stye like you would a pimple, as this will only spread the bacteria.

Problems with eyelashes:Eyelashes can grow inward instead of outward, rubbing against the eye. This is called trichiasis, which often occurs after infection, injury, or other problems.

Blepharitis:This condition causes swollen eyelids, a stinging and watery sensation in the eyes, redness, and itching. It can be caused by infection, rosacea, or an allergy. The condition usually resolves on its own, but treatment can help speed up recovery.