What causes a sudden red blood spot on the white of the eye?

Red blood patches appearing on the white of the eye are referred to as subconjunctival hemorrhage, usually caused by rupture of blood vessels in the conjunctiva. This condition may be triggered by several factors: 1. Eye trauma: Increased pressure in the eye during activities such as rubbing the eyes, coughing, sneezing, or strenuous exercise. 2. Hypertension: Elevated blood pressure can weaken blood vessels, making them more prone to bleeding. 3. Eye inflammation or infection: Conditions such as conjunctivitis or blepharitis can cause local vascular inflammation. 4. Medication effects: Certain medications, such as anticoagulants, may increase the risk of bleeding. 5. Age-related vascular changes: With aging, blood vessels tend to become more fragile. 6. Spontaneous hemorrhage: In some cases, subconjunctival hemorrhage may occur without any identifiable cause. Please note, if the red patch persists or is accompanied by symptoms such as vision loss, pain, or increased discharge, prompt medical attention is advised.