There are many blood vessels that run in between your conjunctiva (the clear surface of your eye) and sclera (the white of your eye). Subconjunctival haemorrhage happens due to some of these tiny blood vessels bursting and bleeding.
In most cases, there isn't a clear cause, but causes can include:
- an eye injury or head injury
- coughing, sneezing or vomiting
- eye rubbing
- high blood pressure
- a bleeding disorder or a tendency to bleed easily
- medicines such as an anticoagulant, eg, aspirin
- strenuous activity, eg, heavy lifting.