Red Eye
Basics
Description
Description
- May be caused by almost any eye disorder
- Often benign; but may represent systemic disease
- Caused by vascular engorgement of conjunctiva
- Main causes:- Inflammatory
- Allergic
- Infection
- Trauma
 
- Conjunctivitis is the most common etiology
Etiology
Etiology
- Inflammatory:- Uveitis:- Anterior and posterior
 
- Iritis- Perilimbic injection
 
- Episcleritis- Common but generally benign
 
- Scleritis- Uncommon, inflammation of the sclera
 
- Systemic inflammatory reactions
 
- Uveitis:
- Allergic:- Due to histamine release and increased vascular permeability, resulting in:- Swelling of conjunctiva (chemosis)
- Watery discharge
- Pruritus
- Usually bilateral
 
 
- Due to histamine release and increased vascular permeability, resulting in:
- Infectious:- Keratitis
- Infectious conjunctivitis
- Orbital cellulitis:- Generally spread from sinus, skin, or blood
 
- Dacryocystitis:- As result of lacrimal duct blockage
 
- Canaliculitis
- Endophthalmitis:- Intraocular infection, may be post op
 
 
- Traumatic:- Corneal abrasion
- Subconjunctival hemorrhage (SCH)
- Foreign body
- Occult perforation
 
- Other:- Pinguecula and pterygium, hemorrhage, blepharitis, dry eye (dysfunctional tear) syndrome, acute angle-closure glaucoma, ophthalmia neonatorum, conjunctival tumor
 
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Citation
Schaider, Jeffrey J., et al., editors. "Red Eye." 5-Minute Emergency Consult, 6th ed., Lippincott Williams & Wilkins, 2020. Emergency Central, emergency.unboundmedicine.com/emergency/view/5-Minute_Emergency_Consult/307317/all/Red_Eye. 
Red Eye. In: Schaider JJJ, Barkin RMR, Hayden SRS, et al, eds. 5-Minute Emergency Consult. Lippincott Williams & Wilkins; 2020. https://emergency.unboundmedicine.com/emergency/view/5-Minute_Emergency_Consult/307317/all/Red_Eye. Accessed October 31, 2025.
Red Eye. (2020). In Schaider, J. J., Barkin, R. M., Hayden, S. R., Wolfe, R. E., Barkin, A. Z., Shayne, P., & Rosen, P. (Eds.), 5-Minute Emergency Consult (6th ed.). Lippincott Williams & Wilkins. https://emergency.unboundmedicine.com/emergency/view/5-Minute_Emergency_Consult/307317/all/Red_Eye
Red Eye [Internet]. In: Schaider JJJ, Barkin RMR, Hayden SRS, Wolfe RER, Barkin AZA, Shayne PP, Rosen PP, editors. 5-Minute Emergency Consult. Lippincott Williams & Wilkins; 2020. [cited 2025 October 31]. Available from: https://emergency.unboundmedicine.com/emergency/view/5-Minute_Emergency_Consult/307317/all/Red_Eye.
* Article titles in AMA citation format should be in sentence-case
TY  -  ELEC
T1  -  Red Eye
ID  -  307317
ED  -  Barkin,Adam Z,
ED  -  Shayne,Philip,
ED  -  Rosen,Peter,
ED  -  Schaider,Jeffrey J,
ED  -  Barkin,Roger M,
ED  -  Hayden,Stephen R,
ED  -  Wolfe,Richard E,
BT  -  5-Minute Emergency Consult
UR  -  https://emergency.unboundmedicine.com/emergency/view/5-Minute_Emergency_Consult/307317/all/Red_Eye
PB  -  Lippincott Williams & Wilkins
ET  -  6
DB  -  Emergency Central
DP  -  Unbound Medicine
ER  -  

 5-Minute Emergency Consult
5-Minute Emergency Consult

