Nick, scrape, or scratch your skin, and it's likely to bleed. Your eyes are very much the same. Illnesses and injuries can cause the front, middle, or back of your eye to bleed.

Common causes of eye bleeding include:

Broken blood vessels. (Learn more)

Traumatic eye injuries. (Learn more)

Infections, including herpes and pink eye. (Learn more)

Blood in your eye isn't always a medical emergency. Sometimes, you don't even need to see a doctor when your eyes are flecked with red.

But if you're ever concerned about your eyes, make an appointment. Symptoms like flashing lights, eye strain, poor night vision, or itchy eyes should prompt you to visit a professional. (Learn more, Should You See a Doctor?)

What Causes Broken Blood Vessels?

man with one red eye staring at camera

Like most of your body, your eye relies on blood for survival. The liquid delivers crucial nourishment and oxygen while whisking toxins away. Many tiny blood vessels line the white part of your eye (the sclera). When one of them breaks, it's known as a subconjunctival hemorrhage.

These burst vessels rarely hurt. You may not even know you have one until you look in the mirror or someone near you points out the problem.

Eye blood vessels are delicate, and they're surprisingly easy to break. Experts say you can develop a subconjunctival hemorrhage after:

  • Bumping, rubbing, or poking your eye.
  • Coughing.
  • Sneezing.
  • Straining.
  • Vomiting.

Diseases that weaken blood vessels, including high blood pressure, can cause bleeding in your eye. Blood thinners may also be to blame if you notice redness forming.

Typically, these burst blood vessels release only a drop or two of blood. But that fluid is pinched between the layers of the eye, and it can bulge outward. You might feel the injury when you blink, and you can be tempted to pinch or squeeze to make the fluid go away.

Don't take matters into your own hands. With time and patience, your body will absorb the errant blood and restore your eye to health. But, Mayo Clinic says, your doctor may want to check your eye if the bleeding was caused by a poke, pinch, or another form of trauma.

If you deal with this issue repeatedly, your doctor might want to investigate and treat the underlying cause. Addressing your high blood pressure, for example, could keep future eye bleeds from taking hold.

Traumatic Eye Injuries Can Cause Bleeding

Sports, home improvement projects, and physical altercations all put your eye health at risk. If you take a direct blow to the eye, you can develop a bleeding issue within your eye.

Common traumatic injuries that cause bleeding include:

  • Black eyes. If a fist comes into contact with your eye, the area around the globe can bleed and swell. The American Academy of Ophthalmology says that black eyes don't always come with bleeding eyes. Sometimes, just the external tissues are harmed. But anytime you have a black eye, your doctor may want to check the globe too, just to ensure you're not bleeding there.
  • Lacerations. Your eyelids should close and protect your eye when something dangerous appears. But sometimes, your lids don't move fast enough. If the sclera of your eye is sliced or punctured, bleeding can occur.
  • Orbital fracture. Eye globes are encased in bony structures for protection. A hard impact can break those bones. The American Academy of Ophthalmology says symptoms include blurry vision, swelling, numbness, and pain. Bleeding in the sclera is another common symptom with these fractures.

Traumatic injuries can cause bleeding in the sclera or in the structures around the eye. But some also cause blood to collect in the front of your eye. This kind of bleeding is known as hyphema, and it is serious. It's also painful, so if you have one, you probably know it.

The American Academy of Ophthalmology says a hyphema is treated with:

  • Eye shields. They protect your eye from future pokes and bumps as tissues heal.
  • Rest. Your body needs time to mend, and you might be asked to stop exercising, working, or both. Sitting quietly with your head elevated can help the blood to drain.
  • Medications. Eye drops can reduce swelling, ease pain, and help tissues to heal.

If your injury is severe, your doctor might ask you to enter the hospital for around-the-clock care. If things don't get better, you may need surgery. Otherwise, your doctor will monitor your healing in a series of appointments.

Infections Can Make Your Eyes Bleed

eyes shut tight

Bacterial and viral cells love warm, moist environments. Your eyes are perfect host spaces for invaders, and once they arrive, they can set up shop and cause tissue damage.

Two types of infections are associated with bleeding in the eyes.

  • Herpes: This common virus can cause ulcers and inflammation. The eye may look uncomfortable, but often, the ulcers aren't painful, experts While there's no cure for the condition, medications may help to reduce the frequency of outbreaks.
  • Pink eye: This condition, also known as conjunctivitis, causes inflammation of the sclera. As the tissues swell, blood vessels are easier to see. That can make it seem as though your eye is filled with blood. This condition will heal itself without treatment, but you should wash your hands carefully, so you don't give the issue to someone else.

Should You See a Doctor?

Seeing blood in your eyes can be frightening, and you might be tempted to call your doctor every time it happens. While that isn't always necessary, it isn't a bad practice.

Your eye doctor can check your eyes and determine why blood is moving outside of vessels and into your eye. As we've mentioned, some bleeding issues require medications and therapy, and you can only get those from a doctor. When you're not sure, it's always best to ask.

And remember that bleeding in the eye isn't the only ocular problem you might face. Your eyes are delicate, and some serious conditions (like glaucoma) come with subtle symptoms that are easy to miss.

You should consider an eye appointment if you notice:

  • Disturbances in your visual field. Flashes of light, floaters, or spots could all indicate an underlying eye health problem.
  • Changes in your vision. If you can't see while driving at night, or you find that you're squinting to read, you can benefit from an eye appointment.
  • Discomfort. If you develop eye strain or dizziness, you might need help with your vision.

These issues may not cause dramatic concerns, like bleeding. But they can be symptoms of serious illnesses, so it's best to make an appointment when you notice them.

 

References

Medical Definition of Blood in the Eye. (December 2018). MedicineNet.

What Causes a Red Spot on the Eye? Medical News Today.

Subconjunctival Hemorrhage (Broken Blood Vessel in Eye). (August 2019). Mayo Clinic.

What Is a Black Eye? (May 2019). American Academy of Ophthalmology.

Hyphema Treatment. (May 2019). American Academy of Ophthalmology.

What Is an Orbital Fracture? (September 2017). American Academy of Ophthalmology.

What Does Eye Herpes Look Like? Medical News Today.

Pink Eye: Usually Mild and Easy to Treat. (March 2019). Centers for Disease Control and Prevention.

8 Signs You Might Need an Eye Exam. VSP.