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Christopher J. Brady

, MD, Wilmer Eye Institute, Retina Division, Johns Hopkins University School of Medicine

Last review/revision May 2021 | Modified Sep 2022
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Excess tearing may cause a sensation of watery eyes or result in tears falling down the cheek (epiphora).

Pathophysiology of Tearing

Etiology of Tearing

Overall, the most common causes 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.

Increased tear production

The most common causes are

Any disorder causing conjunctival or corneal irritation can increase tear production (see table Some Causes of Tearing Some Causes of Tearing Some Causes of Tearing ). However, most patients with corneal disorders that cause excess tearing (eg, corneal abrasion Corneal Abrasions and Foreign Bodies Corneal abrasions are self-limited, superficial epithelial defects. (See also Overview of Eye Trauma.) The most common corneal injuries are retained foreign bodies and abrasions. Improper use... read more Corneal Abrasions and Foreign Bodies , corneal ulcer Corneal Ulcer A corneal ulcer is a corneal epithelial defect with underlying inflammation usually due to invasion by bacteria, fungi, viruses, or Acanthamoeba. It can be initiated by mechanical trauma... read more Corneal Ulcer , corneal foreign body Corneal Abrasions and Foreign Bodies Corneal abrasions are self-limited, superficial epithelial defects. (See also Overview of Eye Trauma.) The most common corneal injuries are retained foreign bodies and abrasions. Improper use... read more Corneal Abrasions and Foreign Bodies , keratitis) or with primary angle-closure glaucoma Angle-Closure Glaucoma Angle-closure glaucoma is glaucoma associated with a physically obstructed anterior chamber angle, which may be chronic or, rarely, acute. Symptoms of acute angle closure are severe ocular pain... read more or anterior uveitis Overview of Uveitis Uveitis is defined as inflammation of the uveal tract—the iris, ciliary body, and choroid. However, the retina and fluid within the anterior chamber and vitreous are often involved as well.... read more Overview of Uveitis present with eye symptoms other than tearing (eg, eye pain, redness). Most people who have been crying do not present for evaluation of tearing.

Decreased nasolacrimal drainage

The most common causes are

Nasolacrimal drainage system obstruction may be caused by strictures, tumors, or foreign bodies (eg, stones, often associated with subclinical infection by Actinomyces). Obstruction can also be a congenital malformation. Many disorders and drugs can cause stricture or obstruction of nasolacrimal drainage.


Other causes of nasolacrimal drainage stricture or obstruction include

Evaluation of Tearing


History of present illness addresses the duration, onset, and severity of symptoms, including whether tears drip down the cheek (true epiphora). The effects of weather, environmental humidity, and cigarette smoke are ascertained.

Review of symptoms should seek symptoms of possible causes, including itching, rhinorrhea, or sneezing, particularly when occurring perennially or after exposure to specific potential allergens (allergic reaction); eye irritation or pain (blepharitis Blepharitis Blepharitis is inflammation of the eyelid margins that may be acute or chronic. Symptoms and signs include itching and burning of the eyelid margins with redness and edema. Diagnosis is by history... read more Blepharitis , corneal abrasion Corneal Abrasions and Foreign Bodies Corneal abrasions are self-limited, superficial epithelial defects. (See also Overview of Eye Trauma.) The most common corneal injuries are retained foreign bodies and abrasions. Improper use... read more Corneal Abrasions and Foreign Bodies , irritant chemicals); and pain near the medial canthus (dacryocystitis Dacryocystitis Dacryocystitis is infection of the lacrimal sac that sometimes leads to abscess formation. The usual cause is a staphyloccocal or streptococcal species, typically as a consequence of nasolacrimal... read more Dacryocystitis ). Other symptoms are of lower yield but should be sought; they include positional headache, purulent rhinorrhea, nocturnal cough, and fever (sinusitis Sinusitis Sinusitis is inflammation of the paranasal sinuses due to viral, bacterial, or fungal infections or allergic reactions. Symptoms include nasal obstruction and congestion, purulent rhinorrhea... read more Sinusitis , granulomatosis with polyangiitis Granulomatosis with Polyangiitis (GPA) Granulomatosis with polyangiitis is characterized by necrotizing granulomatous inflammation, small- and medium-sized vessel vasculitis, and focal necrotizing glomerulonephritis, often with crescent... read more Granulomatosis with Polyangiitis (GPA) ); rash (Stevens-Johnson syndrome Stevens-Johnson Syndrome (SJS) and Toxic Epidermal Necrolysis (TEN) Stevens-Johnson syndrome and toxic epidermal necrolysis are severe cutaneous hypersensitivity reactions. Drugs, especially sulfa drugs, antiseizure drugs, and antibiotics, are the most common... read more Stevens-Johnson Syndrome (SJS) and Toxic Epidermal Necrolysis (TEN) ); cough, dyspnea, and chest pain (sarcoidosis Sarcoidosis Sarcoidosis is an inflammatory disorder resulting in noncaseating granulomas in one or more organs and tissues; etiology is unknown. The lungs and lymphatic system are most often affected, but... read more Sarcoidosis ); and epistaxis, hemoptysis, polyarthralgias, and myalgias (granulomatosis with polyangiitis).

Past medical history asks about known disorders that can cause tearing, including granulomatosis with polyangiitis, sarcoidosis, and cancer treated with chemotherapy drugs; disorders that cause dry eyes Keratoconjunctivitis Sicca Keratoconjunctivitis sicca is chronic, bilateral desiccation of the conjunctiva and cornea due to an inadequate tear film. Symptoms include itching, burning, irritation, and photophobia. Diagnosis... read more Keratoconjunctivitis Sicca (eg, rheumatoid arthritis, sarcoidosis, Sjögren syndrome Sjögren Syndrome Sjögren syndrome is a relatively common chronic, autoimmune, systemic, inflammatory disorder of unknown cause. It is characterized by dryness of the mouth, eyes, and other mucous membranes ... read more Sjögren Syndrome ); and drugs, such as echothiophate, epinephrine, and pilocarpine. Previous ocular and nasal history, including infections, injuries, surgical procedures, and radiation exposure, is ascertained.

Physical examination

Examination focuses on the eye and surrounding structures.

The face is inspected; asymmetry suggests congenital or acquired obstruction of nasolacrimal duct drainage. When available, a slit lamp should be used to examine the eyes. The conjunctivae and corneas are inspected for lesions, including punctate spots, and redness. The cornea is stained with fluorescein and examined. The lids are everted to detect hidden foreign bodies. The eyelids, including the lacrimal puncta, are closely inspected for foreign bodies, blepharitis, hordeola, ectropion, entropion, and trichiasis. The lacrimal sac (near the medial canthus) is palpated for warmth, tenderness, and swelling. Any swellings are palpated for consistency and to see whether pus is expressed.

The nose is examined for congestion, purulence, and bleeding.

Red flags

The following findings are of particular concern:

  • Repeated, unexplained episodes of tearing

  • Hard mass in or near the nasolacrimal drainage structures

Interpretation of findings

Findings that suggest obstruction of nasolacrimal drainage include:

  • Tears running down the cheek (true epiphora)

  • Absence of a different specific cause

For a list of common causes that may be evident from the clinical evaluation, see table Some Causes of Tearing Some Causes of Tearing Some Causes of Tearing .


Testing is often unnecessary because the cause is usually evident from the examination.

Schirmer test with a large amount of wetting (eg, > 25 mm) suggests an evaporative dry eye Etiology Etiology as the etiology of tearing. Schirmer test with very little wetting (< 5.5 mm) suggests an aqueous tear-deficient dry eye Etiology Etiology . Usually, Schirmer test is done by an ophthalmologist to ensure it is done and interpreted correctly.

Probing and saline irrigation of the lacrimal drainage system can help detect anatomic obstruction of drainage, as well as stenosis due to complete obstruction of the nasolacrimal drainage system. Irrigation is done with and without fluorescein dye. Reflux through the opposite punctum (eg, the eye's upper punctum if the lower punctum was irrigated) or canaliculus signals fixed obstruction; reflux and nasal drainage signify stenosis. This test is considered adjunctive and is done by ophthalmologists.

Treatment of Tearing

Underlying disorders (eg, allergies, foreign bodies, conjunctivitis) are treated.

The use of artificial tears paradoxically lessens reflex tearing when dry eyes or corneal epithelial defects are the cause.

Congenital nasolacrimal duct obstruction often resolves spontaneously. In patients < 1 year, manual compression of the lacrimal sac 4 or 5 times a day may relieve the distal obstruction. After 1 year, the nasolacrimal duct may need probing with the patient under general anesthesia. If obstruction is recurrent, a temporary drainage tube may be inserted.

In acquired nasolacrimal duct obstruction, irrigation of the nasolacrimal duct may be therapeutic when underlying disorders do not respond to treatment. As a last resort, a passage between the lacrimal sac and the nasal cavity can be created surgically (dacryocystorhinostomy).

In cases of punctal or canalicular stenosis, dilation is usually curative. If canalicular stenosis is severe and bothersome, a surgical procedure that places a glass tube leading from the caruncle into the nasal cavity can be considered.

Geriatrics Essentials

Idiopathic age-related nasolacrimal duct stenosis is the most common cause of unexplained epiphora in older patients; however, tumors should also be considered.

Key Points

  • If tears do not run down the cheek, dry eyes is often the cause.

  • If tears run down the cheek, obstruction of nasolacrimal drainage is likely.

  • Testing (dacryocystography, CT, nasal endoscopy) is often unnecessary but may be needed when surgery is being considered or occasionally to detect an abscess.

Drugs Mentioned In This Article

Drug Name Select Trade
Phospholine Iodide
Adrenaclick, Adrenalin, Auvi-Q, Epifrin, EpiPen, Epipen Jr , Primatene Mist, SYMJEPI, Twinject
Adsorbocarpine, Akarpine, Isopto Carpine, Ocu-Carpine, Pilocar, Pilopine HS, Salagen, Vuity
AK-Fluor, Fluorescite, Fluorets , Fluor-I-Strip, Fluor-I-Strip A.T., Ful-Glo, Ophthalmicflur
Advanced Eye Relief, Akwa Tears, Akwa Tears Renewed, Alcon Tears, Artificial Tears, Bion Tears, Blink Tears, Clear eyes, Clear eyes Advance Dry and Itchy Relief, Clear eyes Outdoor Dry Eye Protection, Eye Lubricant , FreshKote, Gen Teal Moderate to Severe, GenTeal , GenTeal Mild, GenTeal Moderate, GenTeal PF, GenTeal Severe, GenTeal Tears Mild, GenTeal Tears Severe Dry Eye, Gonak, Goniosoft, Hypo Tears , Isopto Tears, LiquiTears, LubriFresh P.M., Moisture Eyes, Moisture Eyes Preservative Free, Murine, Natural Balance Tears, Nature's Tears, Opti-Free, Puralube Tears, Refresh, Refresh Celluvisc, Refresh Endura, Refresh Lacri-Lube, Refresh Liquigel, Systane, Systane Balance, Systane Complete, Systane Ultra, Teargen, Tears Naturale Forte, Tears Naturale Free, Tears Naturale II, Tears Renewed , TheraTears, Visine Dry Eye Relief, Visine Maximum Redness Relief, Visine Pure Tears, Visine Tears, Visine Tired Eye Relief, Viva
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