A blood spot in your eye is almost always a subconjunctival hemorrhage, a tiny broken blood vessel on the white surface of the eye. It looks alarming but is rarely serious. The blood pools under the clear membrane covering your eye (the conjunctiva), creating a bright red patch that you or someone else notices suddenly, often with no pain or vision changes at all.
This is one of the most common eye conditions. A large population study in Taiwan found it affects roughly 1 in 167 people each year. It peaks in the 60 to 69 age group, where the rate is nearly four times higher than in people under 20, and it occurs slightly more often in women than men.
Why the Blood Vessel Breaks
The conjunctiva is packed with tiny, fragile blood vessels. When one of them ruptures, blood leaks into the space between the membrane and the white of your eye. Because there’s nowhere for the blood to go, it spreads out and becomes very visible. You can think of it like a bruise, just in a spot where you can actually see it happen.
The most common physical triggers are sudden spikes in pressure inside those small vessels. A hard sneeze, a violent coughing fit, heavy lifting, straining on the toilet, or vomiting can all do it. Rubbing your eyes forcefully is another frequent cause. Contact lens wearers sometimes trigger a bleed during insertion or removal. In many cases, people wake up with a blood spot and never identify a specific trigger at all.
Medical Conditions That Raise Your Risk
High blood pressure is one of the strongest risk factors. The same Taiwan study found that hypertension raised the odds of developing a blood spot by about 36%. Chronically elevated blood pressure weakens small vessel walls throughout the body, including in the eye, making them more prone to rupture under even mild strain.
Diabetes is also a recognized risk factor. Over time, high blood sugar damages the lining of tiny blood vessels, making them more fragile. Bleeding disorders, particularly conditions that lower your platelet count (the cells that help blood clot), increase risk by a similar margin. If you’re getting blood spots repeatedly and don’t know why, these are the conditions worth investigating.
Medications That Increase Bleeding
Blood thinners are a well-established trigger. This includes prescription anticoagulants as well as over-the-counter aspirin. The population data showed that regular aspirin use was significantly associated with subconjunctival hemorrhage, raising the odds by about 9%. That’s a modest increase for any individual, but it helps explain why blood spots seem to happen more easily once you start taking daily aspirin or a prescribed blood thinner.
Supplements with blood-thinning properties, like fish oil or ginkgo biloba, can have a similar effect. If you’re on any combination of these medications or supplements, a blood spot is more likely but still not dangerous on its own.
What Healing Looks Like
A subconjunctival hemorrhage clears on its own, typically within a few days to a few weeks. No treatment speeds this up. Your body reabsorbs the blood gradually, the same way it resolves a bruise elsewhere on your body.
As it heals, the bright red patch often shifts through shades of orange, yellow, and green before disappearing entirely. Larger blood spots take longer to clear. During this process you might notice mild scratchiness or a feeling of something in your eye. Artificial tears can help soothe that irritation, but they don’t affect the healing timeline itself. Avoid rubbing the eye, which could delay healing or trigger a new bleed.
Blood Spots That Need Attention
Most blood spots are completely harmless, but a few patterns deserve a closer look. Pain is the most important red flag. A standard subconjunctival hemorrhage doesn’t hurt. If you have significant eye pain along with the red patch, something else may be going on, including a deeper bleed inside the eye (called a hyphema) or elevated eye pressure.
Any change in your vision, even mild blurriness, is another signal to take seriously. The same goes for a blood spot that follows direct trauma to the eye or head, since that could indicate injury beyond a simple surface vessel break. Bleeding from the gums or easy bruising elsewhere on your body at the same time suggests a broader clotting problem.
If you keep getting blood spots repeatedly over weeks or months with no obvious physical trigger like coughing or heavy lifting, it’s worth having your blood pressure checked and asking about a basic blood workup. Recurrent hemorrhages can be an early visible sign of uncontrolled hypertension, a platelet disorder, or a clotting issue that hasn’t been diagnosed yet.
Preventing Recurrences
You can’t eliminate the risk entirely, but you can reduce it. Managing blood pressure is the single most impactful step, since hypertension weakens the very vessels involved. If you have diabetes, tight blood sugar control protects small vessels throughout your body, including in your eyes. Avoiding forceful eye rubbing helps, especially if you wear contacts or have allergies that make your eyes itch.
For strain-related triggers, exhaling during heavy lifts rather than holding your breath reduces the pressure spike that can burst a vessel. Treating chronic coughs or constipation removes two of the most common physical causes. If you take blood thinners, there’s no reason to stop them over a blood spot alone, but knowing that they raise your baseline risk helps you understand why it happened.