A broken blood vessel in the eye, often called a subconjunctival hemorrhage, appears as a bright red patch on the white of the eye and looks alarming but is usually harmless. It happens when a small blood vessel just under the clear surface of the eye breaks and leaks a little blood into the space between the white of the eye and the clear covering of the white of the eye. This guide explains what causes broken blood vessels in your eye, how to tell them apart from more serious redness, and what you can expect as it heals.
What a Broken Blood Vessel in the Eye Looks Like
When a tiny blood vessel beneath the clear outer layer of the eye bursts, blood spreads between the sclera and the conjunctiva. This produces a sharply defined red patch that does not typically affect vision or cause pain. It often appears after sudden increases in pressure in the head and neck veins, and unlike redness from irritation or infection, the redness is localized and does not fade quickly with over-the-counter redness removers. Most people discover it when looking in the mirror or by someone pointing it out.
Common Causes and Triggers
In many cases, no specific injury is identified, and the cause is benign. Everyday actions and conditions that raise pressure in the head and neck veins or weaken small blood vessels can lead to a broken vessel. Factors that commonly contribute include coughing, sneezing, vomiting, or straining during bowel movements; vigorous nose blowing; heavy lifting or intense exertion; rubbing the eyes forcefully; and eye surgery or contact lens insertion. Minor unnoticed trauma from rubbing or from an object briefly touching the eye can also be responsible.
Medical Conditions and Medications That Increase Risk
Some underlying conditions and medications make blood vessels more fragile or raise pressure inside the body. These include high blood pressure, diabetes, blood clotting disorders or use of blood thinners, frequent or intense sun exposure that weakens vessel walls, and medications that affect clotting such as aspirin, ibuprofen, or certain supplements. If broken vessels happen often without an obvious trigger, it can be helpful to review these factors with a clinician.
- Persistent high blood pressure or uncontrolled stress
- Blood-thinning medications or overuse of pain relievers
- Frequent or vigorous eye rubbing
- Recent eye surgery or procedures
- Chronic coughing or vomiting due to illness
When It Is Likely Harmless
In most people, a single, clearly defined red patch with no pain, no changes in vision, and no discharge is harmless. The redness may start bright red and gradually shift to yellow or green as the body reabsorbs the blood, much like a healing bruise on the skin. This process can take one to three weeks. Simple self care, such as using lubricating eye drops for comfort and avoiding further rubbing, supports normal healing and is usually sufficient.
Differentiating From Other Causes of Red Eye
Not all red eyes are subconjunctival hemorrhages, and confusing them can delay proper care. A broken vessel typically causes a uniform red patch without itching, discharge, or blurred vision, whereas pink eye often brings watery or sticky discharge and grittiness; a stye produces localized swelling and tenderness at the lid edge; and uveitis or iritis may cause deeper aching, light sensitivity, and small changes in pupil shape or vision. If redness is accompanied by pain, vision changes, light sensitivity, or spreading discharge, see an eye care professional promptly.
When to Seek Medical Advice
Although most cases resolve on their own, certain signs suggest a need for evaluation. You should consider contacting a clinician or eye care professional if the red eye is painful, involves vision changes, or is accompanied by light sensitivity or significant discharge. Recurrent hemorrhages, large or expanding areas of redness, or bleeding that does not improve within a few weeks may also warrant medical review, as they can point to underlying bleeding or blood pressure issues. In most situations, however, a single episode without these features can be observed and managed with simple care.