A blood vessel in your eye can break from something as simple as a hard sneeze, a coughing fit, or rubbing your eyes too vigorously. The result is a bright red patch on the white of your eye called a subconjunctival hemorrhage. It looks alarming, but it’s painless, doesn’t affect your vision, and typically clears up on its own within one to two weeks.
What Actually Happens When a Vessel Breaks
The white part of your eye is covered by a thin, clear membrane called the conjunctiva. Tiny blood vessels run through this membrane, and they’re fragile. When one of these vessels ruptures, blood leaks into the space between the conjunctiva and the white of the eye. Because the blood has nowhere to drain, it pools and spreads, creating that vivid red or crimson patch. It’s essentially a bruise, just in a place where you can see it clearly.
Common Physical Triggers
The most frequent cause is a sudden spike in pressure inside your blood vessels. This happens during what’s called a Valsalva maneuver: any moment when you forcefully exhale against a closed airway, which drives up pressure in the veins of your head and face. You do this more often than you’d think.
Everyday actions that can trigger it include:
- Sneezing or coughing hard, especially during a cold or allergy flare
- Vomiting
- Straining on the toilet during constipation
- Heavy lifting or intense exercise, particularly weight training
- Blowing a musical instrument
- Labor and delivery
- Sexual activity
Any of these can momentarily push enough pressure into the tiny conjunctival vessels to pop one open. For many people, the rupture happens during sleep or some minor strain they don’t even remember, and they only notice the red patch when they look in the mirror the next morning.
Eye Trauma and Contact Lenses
Direct physical contact with the eye is another common cause. Rubbing your eyes aggressively, getting poked or bumped during sports, or even inserting and removing contact lenses roughly can all damage the delicate surface vessels. Foreign objects like dust or an eyelash can trigger aggressive rubbing that leads to a break. If you wear contacts, handling them carelessly or wearing them too long increases the chance of irritation and vessel damage.
Health Conditions That Make It More Likely
Some people break eye blood vessels repeatedly, and the reason often traces back to an underlying health condition. High blood pressure has the strongest association with subconjunctival hemorrhage. Elevated pressure inside your blood vessels makes them more fragile over time, so they rupture more easily under minor stress. Diabetes causes similar vascular fragility throughout the body, including the eye. If you’re getting these hemorrhages frequently without an obvious trigger like coughing or straining, it may be worth having your blood pressure and blood sugar checked.
Blood-thinning medications also raise the risk. People taking anticoagulants like warfarin, or antiplatelet drugs like aspirin, are more prone to bleeding events throughout the body, and the eye is no exception. Research shows that using both an anticoagulant and an antiplatelet together more than doubles the odds of intraocular bleeding compared to using neither. Even over-the-counter supplements like fish oil or high-dose vitamin E can have mild blood-thinning effects. If you notice a broken blood vessel in your eye while taking any of these, the medication is a likely contributing factor.
In about 40% of cases, no clear cause is ever identified. The vessel simply broke.
What the Healing Process Looks Like
The red patch goes through a predictable color cycle, much like a bruise on your skin. For the first one to five days, it stays bright red or crimson. Between days five and ten, the color shifts to purple, brown, or greenish-yellow as your body breaks down the trapped blood. By days 10 to 21, the discoloration gradually fades and the white of your eye returns to normal. Larger hemorrhages take longer to clear than small ones.
There’s no way to speed up the process. Your body reabsorbs the blood at its own pace. If the area feels mildly irritated or scratchy, artificial tears can help with comfort. Avoid rubbing the eye, which could worsen the bleeding or cause a new break. If you take aspirin or another blood thinner for general wellness (not prescribed for a heart condition), you may want to hold off during healing, as it can slow clotting and extend the hemorrhage.
When It’s Something More Serious
A standard broken blood vessel sits on the surface of the eye, in the white area, and causes no pain or vision changes. If your experience is different, the problem may not be a simple subconjunctival hemorrhage.
A condition called hyphema involves bleeding inside the eye itself, between the clear front surface (cornea) and the colored part (iris). With hyphema, it looks like blood is pooling in front of your eye color rather than on the white. The key differences: hyphema hurts, and it causes blurred or distorted vision. It’s typically caused by a direct blow to the eye and requires prompt medical attention to prevent complications like increased eye pressure or vision loss.
You should also pay attention if a broken vessel on the white of your eye happens after significant head or face trauma, if it keeps recurring every few weeks, if you notice vision changes alongside the red patch, or if the hemorrhage doesn’t start fading after two weeks. Recurrent episodes in particular can signal uncontrolled blood pressure, a bleeding disorder, or a medication issue worth investigating.