A subconjunctival hemorrhage is the bleeding under the conjunctiva giving eye redness appearance. It can be caused by increasing eye pressure such as during strong coughing or squeezing/rubbing eyes, or by eye trauma.
A prominent sign is eye redness or red patch on the white part of the eyes without pain.
Treatment: It can heal itself. The eye redness or blood can go away and be as absorbed in 1-2 weeks. However, go to see your doctor if there is eye pain with red eye. If it happens repeatedly, you need to find out the underline condition such as high blood pressure.