A busted blood vessel in the eye is almost always a subconjunctival hemorrhage, a harmless break in one of the tiny blood vessels sitting just beneath the clear membrane that covers the white of your eye. It looks alarming (a bright red patch spreading across the white part) but causes no pain and no vision changes. Most cases heal on their own within two weeks.
The causes range from something as minor as a sneeze to underlying health conditions that weaken blood vessels over time. Here’s what triggers them and when the red spot deserves a closer look.
Sudden Pressure Spikes Are the Most Common Trigger
Anything that sharply raises pressure inside your chest or abdomen can force blood through the delicate capillaries on the surface of your eye. This happens through what’s called the Valsalva maneuver: you bear down against a closed airway, pressure surges upward, and the tiny veins in your eye can’t handle the spike. The vessel wall gives way and blood pools under the conjunctiva.
Everyday actions that create this kind of pressure include:
- Hard coughing or sneezing
- Vomiting
- Straining during a bowel movement
- Heavy lifting or intense physical exertion
- Vigorous sexual activity
- Labor and childbirth
Even less obvious activities can do it. Case reports have linked broken eye vessels to rollercoaster rides and yoga exercises in otherwise healthy adults. If you’ve had a nasty cold with repeated coughing fits, a red eye afterward is not unusual at all.
Rubbing Your Eyes and Contact Lenses
Vigorous eye rubbing applies direct mechanical pressure to the surface vessels and is one of the most frequent causes people overlook. You might rub your eyes harder than usual during allergy season or first thing in the morning without thinking twice about it.
Contact lenses add their own risk. Every time you insert or remove a lens, you press against the eye’s surface. If your eyes are dry, that pressure is more likely to rupture a vessel. Dirty or expired lenses can also trigger conjunctivitis (pink eye), and the resulting inflammation makes blood vessels more fragile and prone to breaking.
Blood Thinners and Certain Medications
Medications that reduce your blood’s ability to clot make it easier for even minor stress on a vessel wall to produce visible bleeding. Aspirin, clopidogrel, warfarin, apixaban, and rivaroxaban have all been linked to intraocular hemorrhage when used alone. The risk climbs further when these drugs are combined, particularly aspirin paired with other blood thinners or warfarin-based triple therapy.
A study using Japan’s national adverse drug event database found that most intraocular hemorrhage events occurred within the first 90 days of starting one of these medications. Younger patients on aspirin and older patients on warfarin appeared especially susceptible. If you take any blood-thinning medication and notice recurrent red spots in your eye, that’s worth mentioning to whoever prescribes the medication.
High Blood Pressure and Diabetes
A one-time broken vessel rarely signals a systemic problem. Recurrent episodes are different. Repeated subconjunctival hemorrhages can indicate high blood pressure, which puts chronic stress on vessel walls throughout your body, including the tiny ones in your eyes. Diabetes damages blood vessels in a similar way, making capillary walls thinner and more likely to leak.
For this reason, it’s standard practice to check blood pressure in anyone who comes in with a broken eye vessel, and to run further tests if the problem keeps happening. A single episode after a sneezing fit needs no workup. A third or fourth episode in a few months might be the first visible clue of an underlying condition.
How a Broken Eye Vessel Heals
There’s no treatment that speeds up recovery. The blood trapped beneath the conjunctiva has to be reabsorbed by your body at its own pace, much like a bruise on your skin. Most spots clear within two weeks, though larger bleeds can linger longer.
As healing progresses, the bright red patch will shift through colors, turning yellowish before fading completely. This is normal and follows the same pattern as a bruise on your arm. If the area feels scratchy or irritated, artificial tears can help with comfort, but they don’t affect healing time.
Avoid rubbing the affected eye, and if you wear contacts, give your eyes a break until the redness resolves. Aspirin and other anti-inflammatory painkillers can interfere with clotting, so skipping them during recovery is a reasonable precaution unless you take them for a medical condition.
When a Red Eye Is Something More Serious
A standard broken blood vessel sits on the white of the eye, causes no pain, and doesn’t affect your vision. If what you’re experiencing doesn’t match that description, the cause may be different.
A hyphema is bleeding inside the eye itself, between the cornea (the clear front surface) and the iris (the colored part). Unlike a surface-level hemorrhage, a hyphema hurts. The blood pools visibly in front of the iris rather than across the white, and it typically follows a direct injury to the eye. Symptoms include blurred or distorted vision, nausea, vomiting, and in children, unusual sleepiness. Nausea and vomiting in particular can mean pressure inside the eye has reached dangerous levels. A hyphema is an emergency that requires immediate care.
Other warning signs that set a serious problem apart from a benign broken vessel:
- Pain in the eye (a simple subconjunctival hemorrhage is painless)
- Any change in vision, including blurriness, double vision, or partial vision loss
- Blood appearing in front of the colored part of your eye rather than on the white
- Bleeding that followed a blow or injury to the eye or head
- New blood accumulating after the initial spot seemed to be fading
A painless red patch on the white of your eye after coughing, sneezing, or straining is almost certainly harmless. It looks worse than it is, and your body will clear it without any help.