A broken blood vessel in the eye, known medically as a subconjunctival hemorrhage, happens when a tiny blood vessel ruptures just beneath the clear surface membrane covering the white of your eye. The result is a bright red patch that looks alarming but is almost always harmless. It’s also remarkably common: a large population study in Taiwan found it occurs in roughly 1 out of every 167 people per year, with rates peaking in adults between 60 and 69 years old.
Why These Blood Vessels Break So Easily
The conjunctiva is the thin, transparent tissue that covers the white part of your eye. Underneath it sits a dense network of extremely small, fragile blood vessels. Because these vessels have very little structural support, even a brief spike in pressure or minor friction can cause one to pop. When that happens, blood leaks into the narrow space between the conjunctiva and the white of the eye (the sclera), spreading out in a flat, vivid red patch. The blood has nowhere to go, so it stays trapped and visible until your body gradually reabsorbs it.
Everyday Physical Triggers
The most common causes are ordinary activities that briefly increase pressure in the blood vessels of your head and face. Sneezing, coughing, vomiting, straining during a bowel movement, and heavy lifting can all generate enough force to rupture a tiny conjunctival vessel. Even bending over can sometimes be enough.
Vigorous eye rubbing is another frequent culprit. So is any direct bump or poke to the eye, even a minor one you might not think twice about. Contact lens wearers face a slightly elevated risk as well. Research published in the American Journal of Ophthalmology found that people who wear contact lenses are more prone to these hemorrhages if they have certain pre-existing changes in the conjunctival tissue, particularly loose or redundant conjunctiva and small, yellowish growths on the eye’s surface called pingueculae. In contact lens wearers, the bleeding tends to show up on the outer (temple) side of the eye.
Medical Conditions That Raise Your Risk
Sometimes a broken blood vessel points to an underlying health issue rather than a one-time physical strain. High blood pressure is one of the most significant risk factors because it puts constant extra force on blood vessel walls throughout the body, including the eye. Diabetes also weakens small blood vessels over time, making them more prone to rupture. If you’re getting broken blood vessels in your eye repeatedly and you don’t know why, it’s worth having your blood pressure and blood sugar checked.
Blood-clotting disorders, whether inherited or acquired, can also make these hemorrhages more frequent. When blood doesn’t clot efficiently, even the smallest vessel tear takes longer to seal, allowing more blood to leak out and creating a larger, more noticeable red spot.
Medications That Increase Bleeding
Blood-thinning medications are a well-known contributor. Anticoagulants (drugs that slow the clotting process) and antiplatelet drugs (which prevent blood cells from clumping together) both make it easier for small vessels to bleed and harder for the bleeding to stop quickly. Common examples include aspirin and prescription blood thinners. If you take any of these and notice a broken blood vessel in your eye, the medication is a likely factor. Don’t stop taking a prescribed blood thinner because of a broken eye vessel, but do mention it to your prescribing doctor if it keeps happening.
Over-the-counter supplements with blood-thinning properties, such as fish oil and vitamin E in high doses, may also play a role in some cases.
Eye Surgery and Injury
A broken blood vessel is a common, expected side effect after eye procedures. Cataract surgery, LASIK, and other operations that involve manipulating the eye’s surface frequently leave patients with a bright red patch that fades over the following weeks. This type of hemorrhage is typically monitored by your surgeon and resolves on its own without any additional treatment.
What Recovery Looks Like
Most broken blood vessels in the eye heal within about two weeks. You’ll notice the bright red color gradually shifting through darker shades, then sometimes taking on a yellowish tint, much like a bruise fading on your skin. The spot may actually look worse before it looks better, spreading slightly as the trapped blood disperses before your body clears it away. No drops, compresses, or treatments speed this process up significantly. Avoiding aspirin and aspirin-containing products during healing can help prevent the spot from growing.
A broken blood vessel doesn’t cause pain, and it doesn’t affect your vision. You might feel a mild scratchy sensation on the surface of the eye, but nothing more.
When a Red Eye Needs Urgent Attention
A standard subconjunctival hemorrhage is painless and limited to the white part of the eye. A more serious condition called a hyphema involves bleeding inside the eye itself, in the space between the cornea and the iris (the colored part). With a hyphema, blood appears to pool in front of your iris rather than on the white of the eye, often settling in a visible layer with darker blood at the bottom and brighter blood on top.
The key differences are straightforward. A hyphema causes pain, while a simple broken blood vessel does not. A hyphema can blur or reduce your vision. And a hyphema may come with nausea and vomiting, which can signal dangerously high pressure inside the eye. If you experience any combination of eye pain, vision changes, or nausea alongside a red eye, that warrants immediate medical evaluation. The same applies if you notice new blood continuing to accumulate or if the bleeding followed a significant blow to the head or face.
Reducing Your Risk of Recurrence
Because most broken blood vessels result from sudden pressure spikes, the most practical prevention strategies involve managing the triggers. Treating chronic coughs, avoiding excessive straining during exercise or bowel movements, and being gentle when rubbing your eyes all help. If you wear contact lenses, proper fit and careful insertion reduce mechanical irritation to the conjunctiva.
For people with recurring episodes, managing underlying conditions makes the biggest difference. Keeping blood pressure well controlled, maintaining stable blood sugar if you have diabetes, and reviewing your medication list with a doctor can all lower the frequency. Women appear to be affected slightly more often than men across most age groups, though the reasons for this aren’t entirely clear.