By Mayo Clinic Staff
Red eye is a common problem that can affect one or both eyes. The redness associated with red eye comes from blood vessels on the surface of your eye that are expanded (dilated) due to some form of irritation or infection.
Seek emergency medical care
Call 911 or your local emergency number for red eye if:
- Your vision changes suddenly
- It is accompanied by severe headache, eye pain, fever or unusual sensitivity to light
- You also experience nausea or vomiting
- It is caused by a foreign object or chemical splashed in your eye
- You suddenly begin to see halos around lights
- You feel as if something is in your eye
- You have swelling in or around your eyes
- You're unable to open your eye or keep your eye open
Make a doctor's appointment
Occasional, brief periods of red eye are usually no cause for worry. If you think the redness is caused by a reaction to over-the-counter eyedrops, try a different brand or take a break from using them.
Contact your doctor for an appointment if you have red eye that doesn't clear up after several days, especially if you have a thick or nearly continuous pus or mucous discharge.
Contact your eye surgeon if you're experiencing eye redness with pain and you've had eye surgery in the past or if you've recently had eye surgery or an eye injection.
Feb. 24, 2016
- AskMayoExpert. Painful or red eye. Rochester, Minn.: Mayo Foundation for Medical Education and Research; 2014.
- Eye pain. Merck Manual Professional Version. http://www.merckmanuals.com/professional/eye-disorders/symptoms-of-ophthalmologic-disorders/eye-pain. Accessed Jan. 4, 2016.
- Marx JA, et al. Red and painful eye. In: Rosen's Emergency Medicine: Concepts and Clinical Practice. 8th ed. Philadelphia, Pa.: Saunders Elsevier; 2014. http://www.clinicalkey.com. Accessed Jan. 4, 2016.
- AskMayoExpert. Conjunctivitis. Rochester, Minn.: Mayo Foundation for Medical Education and Research; 2014.