Why Are My Eyes Red?

Medically Reviewed by Poonam Sachdev on January 28, 2024
7 min read

Red eyes, also known as "bloodshot eyes," happen when the tiny blood vessels on the surface of the whites of your eyes expand, turning the whites of one or both eyes a pink or reddish tint.

The redness can appear in one eye or both. Your eyes can develop redness gradually or all at once.

Multiple conditions cause red eyes. Some of the most common are:


Outdoor triggers include pollen from grasses and trees. Indoor ones include pet dander, dust, and mold. In these cases, your eyes may also:

  • Itch
  • Burn
  • Tear up

You could also have nasal allergy symptoms, such as sneezing and a stuffy nose.

Dry eye

Sometimes, your tears don’t have the texture they should. They might evaporate too fast. And sometimes, your eyes can’t make tears at all. This condition is called dry eye. It can cause pain, ulcers on your cornea, or, in rare cases, some vision loss.

Other symptoms of dry eye include:

  • A gritty feeling
  • A burning feeling
  • Blurry vision
  • Heavy eyelids
  • Not being able to cry
  • Eye fatigue
  • Excess tears, at times when your eyes aren’t dry
  • A stringy discharge
  • Discomfort with contact lenses


Also known as conjunctivitis, pinkeye is when the lining of your eyelid and the white of your eye become inflamed. It might happen because of a virus or bacteria. It’s very common, especially among children, and is usually very contagious. If you think you have pinkeye, see your doctor, wash your hands often, and don’t rub your eyes.

Pinkeye can be caused by:

Allergies. These typically affect both eyes and are caused by a response to an allergen such as pollen, producing itchy, watery eyes and inflammation. 

Environmental irritants. A foreign object or chemical irritant in your eyes can cause a watery or mucous discharge.

Viruses. Cold viruses are a regular culprit, but other viruses including herpes and shingles can cause pinkeye too.

Bacterial infections. These can be a side effect of colds, but unsterilized contacts can introduce bacteria too. Both the viral and bacterial versions of pinkeye are very contagious.

Haemophilus influenzae (H. influenzae). In infants and children, this bacteria can produce pneumonia and may cause eye infections including pinkeye.

 Other symptoms include:

  • More tears than usual
  • Eyes that burn, itch, or feel gritty
  • A white, yellow, or green discharge from your eyes
  • Sensitivity to light
  • A crust on your eyelid or eyelashes

Broken blood vessels

This happens when tiny blood vessels break beneath the surface of your eye. The blood is trapped and makes the white of your eye turn bright red. It can be caused by a strong sneeze, heavy lifting, hard vomiting, or rubbing your eye a little too hard. You may be more likely to have broken blood vessels, also known as a subconjunctival hemorrhage, if you take blood-thinning medication, even a baby aspirin. Broken blood vessels can look scary but are generally harmless. There’s usually no pain.

Broken blood vessels cause other symptoms like:

  • A bright red area on your eye along with the general redness
  • A scratchy feeling


Fluid can build up in the front part of your eye. This causes pressure and can damage your optic nerve. The condition is called glaucoma. It’s the leading cause of blindness for people 60 and over.

Glaucoma is usually painless. An unusual form of acute glaucoma (angle-closure glaucoma) can cause symptoms such as:

  • Severe pain in your eye
  • A headache
  • Decreased or blurred vision
  • Rainbows or halos in your vision
  • Nausea and vomiting


Episcleritis is an inflammation of the episclera, a thin layer of clear tissue on top of the white part of your eye, or sclera. This is the layer between the thin “skin” of the eye and the tough wall of the eyeball.

When the tiny blood vessels in the episclera get irritated or inflamed, they make your eye look red or bloodshot. It usually happens in just one eye but can affect both.

Though the redness may look like pinkeye, there’s no goopy discharge.

There are two types:

Simple: This is the most common. It has two subtypes:

  • Sectoral. The redness appears over part of your eye.
  • Diffuse. The redness appears over all of your eye.

Nodular: This is when a tiny bump (or nodule) forms on your eye. This kind tends to cause more discomfort.

Other causes

Other causes of red eyes include things in the world around you, such as:

  • Chlorine from swimming pools
  • Dust
  • Cigarette smoke
  • Perfume
  • Damage to your cornea by ultraviolet rays (photokeratitis)
  • Ocular rosacea
  • Alcohol or marijuana use

Also, eye conditions like:

  • A scratch, infection, or ulcer on your cornea
  • Cornea inflammation (keratitis)
  • Eyelid inflammation (blepharitis)
  • Inflammation of the colored part of your eye (iritis), the middle layer of your eye (uveitis), or the white part of your eye (scleritis)
  • Chalazions, tiny lumps caused by a blocked or swollen oil gland in the eyelid
  • Styes, an infection of the oil gland
  • Eye injury
  • Complications from eye surgery or contact lens use

Over-the-counter eyedrops that target redness can actually make the problem worse. Your eyes might come to depend on the drops and be even redder after they wear off. They can also dry out your eyes and hide symptoms of health problems.

Red eyes are usually nothing to worry about, as long as they don’t happen often and don’t last long. 

How to treat red eyes

Home remedies can help relieve your symptoms, such as rest, cool compresses, gently washing your eyelids, or lightly massaging them. You might find brief relief in over-the-counter artificial tears that wash and moisten your eyes.

Decongestants and antihistamines can help with itchiness and redness because of allergies. They can sometimes make your eyes feel dry, though, so you should try to also use a lubricating artificial teardrop. If you have a bacterial infection, you might need to take antibiotics.

Prescription and medical treatment for red eyes include:

  • Steroid eye drops or pills
  • Antibiotic medicines including pills, eye drops, or topical treatments around or in your eye 
  • Prescription eye drops for specific conditions such as allergies, dry eye, or glaucoma
  • A laser procedure to treat acute angle-closure glaucoma



Call your doctor if you have red eyes along with:

  • A sudden change in vision
  • Sensitivity to light
  • Sudden halos around lights
  • A severe headache, eye pain, or fever
  • Nausea or vomiting
  • Something in your eye
  • Swelling
  • An inability to keep the eye open

While red eyes can be unsightly, the cause is usually not serious. If they're not infected, you can usually treat cases of red eye with over-the-counter medications or at-home treatments.

Less frequently, red eyes can be a symptom of other, more serious conditions. Untreated infections, inflammation, or eye injury may result in vision changes like glaucoma or cataracts that affect activities of daily living such as driving, or even cause permanent vision loss.


These are some of the ways you can prevent red eyes:

  • Avoid eye makeup or remove it thoroughly each day.
  • Don't rub your eyes, and keep your fingers out of your eyes.
  • If you wear contacts, clean and use them as directed.
  • Avoid irritants like smoke, chemicals, or perfumes, and flush out your eyes immediately if you come into contact with them.
  • Keep mold and dampness in your home at bay by using a dehumidifier.
  • Wash your hands frequently, especially if you've been exposed to someone with an eye infection.
  • Give your eyes frequent breaks from TV, computer, and phone screens (blue light).

Red eyes can usually be treated easily at home or, in case of pinkeye or another infection, by your doctor. Pain, vision changes, recent light sensitivity, or eyelid swelling are all reasons to call your doctor. An ophthalmologist (eye doctor) will be able to diagnose and treat your symptoms before your red eyes turn into something that threatens your vision. 

What is the cause of red eyes?

Injury, infection, and inflammation can all cause red eyes. The redness comes from irritated blood vessels just under the surface of your eye.

Do red eyes mean you're sick?

Sometimes. Your red eyes could be the result of a cold or viral infection. Very rarely, but more seriously, the redness could be caused by a tumor in your eye.

When should I be worried about red eyes?

Call your doctor if your eyes are painful, light sensitive, have a discharge, or your symptoms are accompanied by a fever. You should also call if your vision changes or your red eyes don't get better after a week.