Why you are often in tears: normally, tears in lachrymal gland and sub la chrymal gland will be balanced by tear defecation system or evaporation after winking our eyes. The lacrimal fluid covers the whole Nintendo DS Lite surface of the eyeballs so that they can be maintained moist and comforable, and meanwhile, we can’t feel tear drops. But if the tears are too many or there is something wrong with defecation system, we will feel that we are crying. Too many tears may result from multiple factors, including nerve stimulus.

Foreign body's reflex stimulation; cholinergic drugs and anti-cholinesterase agents of drug effect; certain eye diseases such as glaucoma, eyelids, conjunctiva, iritis and so on. Or the trigeminus and the facial nerves are stimulated. If your eyes secrete exessive lacrimal fluid which could hardly evaprate or excrete, your tears will keep falling all the time.

Also, if tears defecation system goes wrong, such as the lacrimal punctum may position wrong, become narrow or close, its duct linking with the nasolacrimal becomes narrow or obstructed, or the tear tract turns dysfuctional, our tears would not be defecat Old people usually get such symptom, they will cry when in thr front of the wind and get worse under cold weather, even no matter which season and in or out of house.

Snow blindness, also called snow ray ophthalmia, is mainly caused by ultraviolet radiation in the sun light, and it will hurt your cornea if it is reflected from the vast snow ground to your ocular region. Studies ds card have shown that 300 microns ultraviolet radiations of the sun shine on the snow field and are reflected to the eyes, which may lead to snow blindness. Then it appears to be photophobia, shedding tears, inflammation and pain, itching and a sense of foreign body. Therefore, when going out in snow days, it is best to wear sunglasses to prevent the strong rays reflected by snow field form stimulating the ey

Chronical conjunctivitis: it may be one of the main cuases for crying during August and Winter. It could be divided into two sorts, infectious inflammation and uninfectious one. The former is an inflammation caused by pathogenic microorganism. And bacterium, viruses, chlamydia, fungus may all cause diseases. The occurrence of non-infectious chronic conjunctivitis mainly is connected with environment and the habits of using eyes, its prevalence is increasing. Stimulation such as sand wind, dust, smog, harmful gas and often stay up late, sleep insufficiency, excessive smoking, eyestrain, etc all may cause chronic conjunctivitis.

Dry-eyed conjunctivitis: owing to dry eyes glasses , old people will cry frequently. The dry and cold Winter is the popular season for this symptom. Xerophthalmia will decrease the tear secretion, the eyes become dry and uncomfortable. If the surface of eyeball is damaged, the eyes will shed large quantities of tears reflexively. Menopausal women, allergic conjunctivitis patients, people who contracted trachoma at the early age, people who have corneal scarring organization are susceptible to dry eye to lead to flowing tears. The nasolacrimal duct blockage: Many elderly people who are often in tears is due to blockage caused by nasal lacrimal duct. The opening of nasolacrimal duct is at the position of the the lower eyelids which is near the nose while the exit is in the nasal