A subconjunctival hemorrhage is leakage of blood from tiny blood vessels located underneath the thin, clear membrane (conjunctiva) that lies atop the white of the eye (sclera).
The pooling of this blood under the conjunctiva causes the affected area of the sclera to turn bright red. This red area can be quite small, or it can cover the entire white of the eye.
Though subconjunctival hemorrhages look scary, they typically do not cause any vision problems and they resolve without treatment within a week or two.
But any time you develop red eye, you should see an eye doctor to determine if the redness is due to a harmless subconjunctival hemorrhage or a more serious condition, such as an eye infection.
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