eye disorders
Tearing
Etiology of Tearing
Overall, themost commoncauses of tearing are Upper respiratory infection Allergic rhinitis Tearing can be caused by increased tear production or decreased nasolacrimal drainage. In many patients, the cause of tearing can be multifactorial. The most common causes are Upper respiratory infection Allergic Rhinitis None Allergic Conjunctivitis None Keratoconjunctivitis Sicca (reflex tearing produced in response to dryness of the ocular surface) Trichiasis None ). However, most patients with corneal disorders that cause excess tearing (eg, Corneal Abrasions and Foreign Bodies , The most common causes are Idiopathic age-related Dacryostenosis None Dacryocystitis None Ectropion None Nasolacrimal drainage system obstruction may be caused by strictures, tumors, or foreign bodies (eg, stones, often associated with subclinical infection byActinomyces). Obstruction can also be a congenital malformation. Many disorders and medications can cause stricture or obstruction of nasolacrimal drainage. Other causes of nasolacrimal drainage stricture or obstruction include Burns Chemotherapy drugs Eye drops (particularlyechothiophateiodide,epinephrine, andpilocarpine) Infection, including Canaliculitis (eg, caused by Inflammatory disorders ( Sarcoidosis , Injuries (eg, nasoethmoid fractures; nasal, orbital, or endoscopic sinus surgery) Obstruction of nasal outlet despite an intact nasolacrimal system (eg, upper respiratory infection, allergic rhinitis, Sinusitis ) Radiation therapy Stevens-Johnson Syndrome (SJS) and Toxic Epidermal Necrolysis (TEN) None 