Lacrimation

The secretion and discharge of tears from the lacrimal glands, occurring at a normal basal rate or in excessive amounts in response to ocular irritation, inflammation, obstruction, or systemic stimuli.

Causes

• Ocular irritation

  • Dust

  • Sand

  • Wind

  • Bright light

  • Smoke or chemical irritants

  • Onions and other tear-inducing substances

  • Ocular trauma

  • Foreign body on the ocular surface

  • Contact lens irritation

• Tear film disorders

  • Dry eye syndrome causing reflex tear production

  • Tear film instability

• Allergic and inflammatory causes

  • Allergic conjunctivitis

  • Conjunctivitis

  • Blepharitis

  • Keratitis

  • Anterior uveitis

• Infectious causes

  • Bacterial conjunctivitis

  • Viral conjunctivitis

• Lacrimal drainage disorders

  • Blocked nasolacrimal duct

  • Congenital nasolacrimal duct obstruction

  • Scarring of the lacrimal drainage system

• Eyelid disorders

  • Ectropion causing impaired tear drainage

  • Entropion causing corneal irritation and reflex tearing

• Neurological disorders affecting tear regulation

• Facial nerve dysfunction