Managing Subconjunctival Hemorrhage in Acute Care

In emergency medicine, we are trained to be wary of the things that look harmless but carry real danger. High-pressure injection injuries, hydrofluoric acid burns, the “simple” appearing complaints that actually are dangerous. Subconjunctival hemorrhage (thankfully) flips that script. It is one of those findings that looks dramatic, even alarming, both to patients and clinicians, but is typically benign. The challenge is not just recognizing it, but knowing when it truly is as reassuring as it seems.

What You’re Actually Seeing

A subconjunctival hemorrhage is simply bleeding beneath the conjunctiva, the thin, transparent membrane that covers the sclera. When one of the tiny, delicate vessels in this layer ruptures, blood pools in that space and creates the characteristic bright red patch. The key features are reassuring once you know what to look for, and once you see it, you’ll never forget it. These patients have a painless red eye without photophobia, discharge, or vision changes. Many do not even notice it until someone else points it out or they catch their reflection in the mirror.

The causes are often surprisingly benign. Sometimes there is no clear trigger at all. Other times, it is related to a sudden increase in venous pressure. A forceful cough, a bout of vomiting, heavy lifting, or even straining during a bowel movement can be enough to rupture those fragile vessels. Minor trauma such as eye rubbing or contact lens irritation can also play a role. There are also important risk factors to keep in mind, especially in older adults. Hypertension, diabetes, and anticoagulant use can all increase the likelihood of developing a subconjunctival hemorrhage.

Don’t Skip the Story

Even though the diagnosis is usually straightforward, this is not a visit to rush through. The most important part of the encounter is not confirming what the red patch is, but understanding how it got there. A good history matters. Asking about recent vomiting, coughing, or straining can uncover the trigger. Asking about trauma is essential, even if it seems minor at first. And taking a step back to review symptoms more broadly can reveal something more serious. I had a memorable case of a patient who came in “for emergent ophthalmology” due to their scary subconjunctival hemorrhage… after a thorough history, it turns out they got the subconjunctival hemorrhage from vomiting from the vertigo caused by their posterior stroke.

​​Exam Pearls That Matter

The physical exam should reinforce your diagnosis, and your documentation should reflect this. Visual acuity should be normal. The hemorrhage itself should appear flat and well demarcated. Both active and passive eye movements are intact, and there should be no signs of deeper injury. Importantly, there should be no pain, no photophobia, and no changes in the pupil. When those features are present, it is time to pause and reconsider whether this is truly a simple subconjunctival hemorrhage.

It is also important to recognize what this is not. Conditions like hyphema, where blood layers in the anterior chamber, or hemorrhagic chemosis, which can signal serious ocular trauma, require a completely different level of urgency. The distinction comes down to careful observation and documentation. Naming what you see is important, but so is clearly documenting what you do not see.

What to Do (and Not Do)

Once you are confident in the diagnosis and have ruled out dangerous etiologies, management is refreshingly simple. There is no specific treatment required. Most subconjunctival hemorrhages resolve on their own within two to three weeks as the blood is gradually reabsorbed. Artificial tears can help with mild irritation, but reassurance is the main intervention. Patients should be advised to avoid eye rubbing and to take it easy on activities that increase strain. Checking a blood pressure is also a small but meaningful step in reducing patients overall cardiovascular risk moving forward, especially in patients who may not have regular access to care.

For patients on anticoagulation, the presence of a subconjunctival hemorrhage alone does not usually change management. However, it can be a helpful prompt to ensure appropriate follow-up, particularly for those on warfarin who may need INR monitoring.

In the end, this is one of those diagnoses that reminds us how much reassurance matters in the acute care setting. What looks alarming is often benign, but the experience for the patient is still very real. Taking a moment to explain what is happening, what to expect, and when to worry can turn a stressful visit into a reassuring one. And sometimes, that is exactly the kind of care patients need most.