Tearing of the eye is a normal process designed to keep the surface of the eye moisturised and remove any dirt or debris that gets caught in the eye. However, it can at times become excessive where it poses a severe problem in terms of vision, comfort and cosmetic appearance. The medical term for excessive tearing is epiphora and can range from watery eyes to excessive tears to the point where it runs down the cheek. Tearing due to crying is not considered as epihphora.
Tear Production and Control
The lacrimal system is the tearing mechanism of the eye. The tear gland (lacrimal gland) is situated above the outer part of the eye, just under the eyebrow. Tears are produced in this gland and secreted onto the surface of the eye. Any excess tears are drained away through the lacrimal duct which is located on the inner edge of the eye. It collects in the lacrimal sac where it is then flushed out into the nose through the nasolacrimal duct. Any factors that increases tear production or block the drainage of tears will lead to watery eyes.
Causes of Watery Eyes
The most common cause of watery eyes are infections or allergies of the upper respiratory tract. This causes increased tear production and decreases tear drainage. Common infections and allergies that will lead to watery eyes include :
- Colds and flu
- Hay fever
- Acute sinusitis
- Pink eye (conjunctivitis)
- Infection of the nasolacrimal duct and/or lacrimal sac (dacryocystitis)
Other common causes of watery eyes includes :
- Injury to the eye – physical trauma, chemical irritation.
- Environmental irritation – dry, cold weather, air conditioning, air pollution.
- Foreign objects in the eye – dust, sand, contact lens, eye makeup, eye lashes.
- Other causes of nasal congestion and inflammation which blocks the drainage duct.
- Mucus discharge in the eye causing obstruction of the tear drainage system.
- Stye (hordeolum).
- Dry eyes may lead to excessive tear production thereby causing watery eyes.
- Congenital (since birth) or age related deformities of the drainage ducts.
- Tumors in the drainage duct and/or lacrimal sac.
Watery Eye Symptoms
Apart from the excessive tear production, other signs and symptoms may also be present. These include :
- Redness of the eye.
- Itching, burning or pain in or around the eye.
- Nasal congestion.
- Runny nose.
- Blurry vision due to the presence of excessive tears.
- Obstruction of the drainage system can lead to infections of the eye or eyelid with swelling and mucus discharge.
Treatment for Excessive Tearing
You should see an eye doctor (opthamologist) to diagnose the cause of the excessive tearing. For bacterial infections, antibiotics will be required while the swelling may be reduced with steroid eye drops. In severe and chronic cases, eye surgery may be necessary but this is usually a last resort. Avoid using contact lenses if it causes repeated infections or irritates the eye constantly.