Sometimes, blood vessels burst in the eye due to pressure caused by sneezing or coughing, according to WebMD. It can also be caused by vomiting or some other type of straining.
A broken blood vessel in the eye is known as a hemorrhage as stated by the Mayo Clinic. The issue typically goes away on its own without any type of treatment. Sometimes, it can take up to three weeks for the blood to go away completely. Medications used to treat blood clots can cause the issue more frequently. If this problem reoccurs, a person should contact their doctor to ensure something more serious is not going on.