What causes a red spot on the eye?
The conjunctiva is the transparent membrane that covers the surface of the eye. The conjunctiva contains tiny blood vessels that can break or leak after sudden increases in pressure.
In this article, learn more causes red spots on the eyes and how to treat them.
Causes of subconjunctival hemorrhage can include sneezing, coughing, and an injury to the eye.
A red spot on the eye, or subconjunctival hemorrhage, usually occurs as a result of increased blood pressure. In some cases, subconjunctival hemorrhages can appear without any identifiable cause.
A person might not realize they have a subconjunctival hemorrhage until they look in a mirror.
Common causes of a red spot on the eye include:
- excess physical strain
- injury to the eye
- irritation or allergic reactions
- rubbing the eye too hard
Rare causes of subconjunctival hemorrhages include:
Diabetic retinopathy can also lead to a red spot on the eye. This occurs when blood vessels in the eye break due to high blood sugar levels.
Blood from broken or leaking vessels can cause "floaters" or dark spots in the vision. People may not realize they have diabetic retinopathy until it affects their vision.
Symptoms of diabetic retinopathy include:
- blurred vision
- reduced night vision
- seeing colors that appear faded
People who have diabetes can reduce their risk of developing diabetic retinopathy by controlling their blood sugar and blood pressure levels.
If a person is experiencing diabetic retinopathy, they may wish to speak to a doctor about ways to manage underlying diabetes.
Subconjunctival hemorrhages do not usually require treatment. The healing time can vary from a few days to a few weeks, depending on the size of the spot.
People can use artificial tears to relieve irritation or dryness. Artificial tears are available in drug stores, pharmacies, and online.
A doctor may prescribe antibiotic eye drops if the red spot is the result of a bacterial infection.
People should not be alarmed if the red spot changes colors from red to yellow or orange. This is a sign that the hemorrhage is healing. Like a bruise, it may slowly fade over time.
Treatments for diabetic retinopathy include:
- injectable medications to reduce swelling
- laser eye surgery to close leaking blood vessels
- vitrectomy, or surgery that involves removing vitreous gel and blood from the back of the eye
Subconjunctival hemorrhages usually heal over time without medical treatment.
However, people can try these home remedies to relieve uncomfortable symptoms and promote healing:
- applying a warm compress to reduce irritation
- applying a cold compress to reduce swelling
- choosing not to wear contact lenses while the eye heals
- using artificial tears to soothe itching and reduce dryness
- avoiding rubbing the eyes
Image credit: FIP, 2009
Image credit: Iceclanl, 2012
Image credit: Daniel Flather, 2011
Image credit: Masoud Reza Manaviat, Maryam Rashidi and Seyed Mohammad Mohammadi, 2009
When to see a doctor
People should seek medical attention if an injury caused the red spot on their eye or if they have a history of high blood pressure or a bleeding disorder.
People should also seek medical attention if they experience the following as well as the red spot:
- pain in the affected eye
- a headache
- discharge from the eye
- bleeding in both eyes
- changes in vision
- bleeding gums
- bruising around the eye
- multiple subconjunctival hemorrhages
Having multiple subconjunctival hemorrhages might indicate a different underlying medical condition, such as conjunctival amyloidosis.
Conjunctival amyloidosis is a rare eye disorder that causes pink or yellow lesions on the eye or inside the eyelid. It occurs when protein accumulates inside organs and other tissues.
Conjunctival amyloidosis typically stays within the eye and does not involve other organs or tissues.
Although it may look alarming, a red spot on the eye is likely to be a subconjunctival hemorrhage. Typically, subconjunctival hemorrhages do not require medical treatment, and they will not affect a person's vision.
People should see a doctor if they experience pain, impaired vision, or discharge coming from the eye that the red spot is affecting.
Diabetic retinopathy may also cause a red spot on the eye. People who have diabetes can speak with a doctor if they notice any changes in their vision, such as floaters or blurring.