Red, bloodshot eyes can be a sign of several conditions. Although they might look a bit alarming, they’re often caused by a minor eye irritation or condition, like conjunctivitis. To find out more about what causes red eyes and treatments, keep reading.
What is a red eye?
A red, bloodshot eye usually happens when the blood vessels on the surface of the eye — the conjunctiva — expand. Red eyes can be a sign of infection, irritation, inflammation, or a more serious condition if you also experience pain, and increased light sensitivity in the eye.
If redness occurs in small, localized areas or spots, this is sometimes due to an injury. If the entire front of the eye appears reddened, this might be caused by an infection or allergy.
Symptoms of red and bloodshot eyes
Depending on what’s causing your bloodshot eyes, you may also experience some other symptoms. Let’s look at some of the most common ones:
Pain: a sore red eye commonly causing minor discomfort, or more severe irritation in acute cases.
Itching: feeling like you need to scratch your eye or eyelid to ease discomfort.
Swelling: your eyelid may feel puffy or tight, making it hard to open your eye and therefore affecting your vision.
Grittiness: feeling like there’s something in your eye, even if you can’t see anything in it.
Watery eyes: your eyes might also produce excess tears, commonly caused by dryness or irritation.
What causes red eyes?
When it comes to figuring out why your eye is bloodshot or red, if you have no pain, a minor eye condition is usually the cause. These conditions don’t tend to affect your vision, and many often get better within a week or two with minimal intervention.
These conditions could include:
Blepharitis: a common condition which causes redness, swelling and irritation of the eyelids.
A burst blood vessel (subconjunctival hemorrhage): a minor condition which can make the eyes appear red.
Conjunctivitis: a viral or bacterial infection of the thin layer of tissue that covers the front of the eye and inner surfaces of the eyelid.
Dry eyes: insufficient or poor‑quality tears (meaning the eyes don’t produce enough tears, or that they evaporate too quickly), can cause discomfort, soreness and redness. They’re usually treatable with eye drops and home remedies.
Stye: small, painful lumps that form either on or inside the eyelid, which can cause the eye itself to become watery and red.
Alcohol and/or drug misuse: alcohol and substance abuse can result in red, bloodshot eyes which, in some cases, can become chronic.
If you have a painful bloodshot eye or are experiencing sensitivity to light, that could be a sign of something more serious, such as:
Acute angle‑closure glaucoma: an increase in eye pressure resulting in redness, pain, nausea, haloes around lights and blurred vision. Left untreated, it can lead to permanent vision loss.
Corneal ulcers: this can cause redness, light sensitivity, pain and a feeling that there’s something in your eye. Severe cases can result in permanent damage if left untreated.
Scratched eye: redness and pain can be caused by grit getting into the eye. Grit or foreign bodies can often be removed by an eyecare professional.
Anterior uveitis: an inflammation of the front of the eye which may be accompanied by eye pain, light sensitivity and/or additional vision problems.
Scleritis: a form of eye inflammation associated with autoimmune disorders, like rheumatoid arthritis and lupus.
How can I get rid of red eyes?
In many cases bloodshot eyes will clear up on their own without needing any treatment. However, depending on the cause or your symptoms, there are a variety of red eye treatments that can help you to manage symptoms and reduce discomfort.
If you’re concerned about your eye health or are experiencing any of these symptoms, get in touch with your optometrist. In severe cases, further tests and ongoing treatment may be necessary.
Home remedies for bloodshot eyes
Eye drops: over‑the‑counter eye drops can be used to ease dry eyes and soothe irritation.
Cold compresses: gently pressing a cold compress over your eyelids may help reduce inflammation and redness, particularly for allergies like hay fever.
Allergy medication: if an allergic reaction is causing your red eyes, taking antihistamine medication can help address the underlying allergic response and relieve physical symptoms.
Medical treatment
Prescription medication: if home treatments don’t seem to be helping, or the problem is recurring, an optometrist can prescribe medications to treat your red eyes. This may be with eye drops or ointments.
When to seek immediate medical help
Contact your optometrist, healthcare provider or local eye emergency department if:
You have a painful red eye.
You’re experiencing other symptoms, in particular; a bloodshot eye and headaches, reduced vision, sensitivity to light or feeling sick.
You recently injured your eye – especially if something has pierced your eye.
If your symptoms are becoming increasingly worse. This includes seeing halos or rainbows around lights with accompanying eye pain or nausea and vomiting.
Next steps
Having red or bloodshot eyes is a very common eye condition that most of us will experience. Most cases are mild and won’t require any treatment, but sometimes, red eyes could be a sign of other conditions like conjunctivitis or anterior uveitis.
Generally speaking, maintaining good eye and overall health does enough to reduce your risk of red eyes.
We want to help keep your eyes healthy for as long as possible. If your optometrist detects any signs of an eye condition during your eye exam, they will determine an appropriate management plan that suits your needs.
Book an eye examGet answers to your questions
Having a bloodshot eye on one side, rather than in both eyes, is very common and there are plenty of reasons why this might be the case. It may simply be that only one eye has been irritated or injured, or, in the case of a condition like conjunctivitis, one eye may become infected before later spreading to the other. Either way, it’s best to seek advice from your optometrist.
Preventing red eyes all together is unlikely, but there are a few good habits that may help, such as:
Getting enough sleep: tiredness commonly leads to dry, red eyes, so the redness could be a sign that you’re not getting enough sleep. Try to aim for between seven and nine hours each night.
Taking regular breaks from screens: if you find staring at a screen for too long irritates your eyes, like when you’re working or gaming, make sure you take some time away to give your eyes a rest.
Having regular eye exams: your optometrist will look for signs of any eye strain issues and other eye conditions that might be irritating your eyes.
Usually, no. Red eyes are a common condition and for most people, it’s nothing to worry about and won’t require any treatment. However, in some cases, bloodshot eyes can indicate underlying conditions such as conjunctivitis and blepharitis. If you have any other accompanying symptoms like headaches, eye discharge, pain, sensitivity to light and blurred vision, seek advice from an optometrist or healthcare provider.
Noticed a change in your eyesight?
If you have any concerns about your eye health, contact or visit your local optometrist immediately – even if you do not have an appointment.
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