A sudden, bright red patch appearing on the white of the eye is often alarming. This condition, known medically as a subconjunctival hemorrhage, occurs when a tiny blood vessel ruptures just beneath the eye’s surface. While the appearance can suggest a severe injury, the condition is overwhelmingly benign and typically does not signal a serious underlying problem. Understanding the location of the bleed and accompanying symptoms determines whether you should seek professional medical attention.
Understanding Subconjunctival Hemorrhage
A subconjunctival hemorrhage results from a broken capillary in the conjunctiva, the thin, clear membrane covering the sclera (the white part of the eye). This membrane contains small, delicate blood vessels that easily rupture from minor stresses. The blood appears intensely bright red because it is trapped between the conjunctiva and the underlying sclera, keeping it oxygenated and highly visible. Since the blood is contained in this shallow, enclosed space, it cannot spread or drain quickly, giving the hemorrhage its characteristic dense, flat patch appearance.
The condition affects only the surface of the eye and does not involve the cornea, iris, or pupil, meaning it causes no disruption to vision. Aside from the noticeable discoloration, most people experience no other symptoms. However, a mild scratchy or gritty sensation is sometimes reported.
Common Triggers and Risk Factors
The most frequent cause is a sudden, temporary increase in venous pressure within the head or chest. These brief pressure spikes often occur during everyday activities that involve straining, known as Valsalva maneuvers. Common examples include forceful coughing, a vigorous sneeze, vomiting, heavy lifting, or straining during a difficult bowel movement.
Certain medications can increase the risk, particularly anticoagulant and antiplatelet drugs like aspirin or prescribed blood thinners. These medications do not cause the hemorrhage directly but make the capillaries more susceptible to breaking. This susceptibility can lead to a larger or more recurrent bleed.
Warning Signs That Require Immediate Care
While most subconjunctival hemorrhages are harmless, specific accompanying symptoms suggest the bleed may be secondary to a more concerning issue. Seek prompt medical evaluation if the red patch is paired with any noticeable change in vision, such as blurriness, double vision, or visual loss. Significant eye pain or a deep, throbbing ache is not typical and warrants professional assessment. A hemorrhage following direct trauma to the eye or head, such as a blow or a fall, requires immediate medical attention to rule out internal eye damage. If the blood appears to pool over the cornea or near the pupil, this indicates a potentially more serious condition, such as a hyphema, which affects internal eye pressure.
Recurrent hemorrhages, especially those that happen frequently or are bilateral, may signal an underlying systemic issue. These issues include uncontrolled high blood pressure or a blood clotting disorder that needs investigation.
Management and Expected Recovery
When the subconjunctival hemorrhage is determined to be benign, no specific treatment is required because the body naturally reabsorbs the blood. Over-the-counter artificial tears may be used if the eye feels mildly irritated or scratchy, but they do not speed up the healing process. Avoid rubbing the eye and temporarily stop using non-essential medications like aspirin that may prolong the bleeding. Changes to prescribed blood thinners should only be made under a doctor’s guidance.
The healing process is similar to that of a bruise elsewhere on the body, with the color gradually changing as the blood is broken down. The bright red color will often darken, then transition to a yellowish or brownish hue before disappearing completely. The total time for the blood to be fully absorbed and the eye to clear is usually between one and three weeks, depending on the size of the initial hemorrhage.