Red or irritated eye

What is it?

A red eye is when the white part of the eye becomes reddish or pinkish in color due to dilation or swelling of the blood vessels in the area. It is a symptom that can occur in one or both eyes at the same time. Sometimes the red eye is accompanied by itching, swelling, discharge or blurred vision. The fact that the eye becomes red means that there is an ocular inflammation. Therefore, we must take some measures, since among the causes that can provoke this inflammation there are from the most banal to other potentially serious ones that could produce changes in visual acuity.

When should I go to the emergency room?

Entrance of emercgency room. Photo: J. Casanova / ICR

In order not to worry excessively and so that you can assess the degree of urgency of the red eye, you must take into account two factors that can be associated with this symptom:

EYE PAIN: If it exists, you should go to the emergency room, because you may need specific treatment that only an ophthalmologist can administer. This does not necessarily mean that the cause is very serious, but it is advisable to be evaluated and followed up properly.

LOSS OF VISION: It is necessary to go to the emergency room, since loss of vision may mean that the problem is not located on the surface of the eye, but that there is an associated internal problem.

Other symptoms that require a visit to the ophthalmologist:

• yellowish, brown or green mucous secretions, as this could indicate an infection requiring medical treatment;
• excessive sensitivity to light;
• fever or general discomfort;
• duration of redness longer than one week;
• exposure to people suffering from conjunctivitis.

What can I do in the meantime?

If your eyes are red, but you do not have any of the above more serious symptoms, you can try certain palliative measures.

• Application of non-prescription artificial tears.
• Application of non-prescription antihistamine drops, especially if you tend to suffer from seasonal allergies.
• Application of cold packs or clean cloths over closed eyes a couple of times a day.
• Avoidance of irritating or redness-triggering elements, such as tobacco smoke, gas, pollen, dust, chlorine or animal dander.
• Do not rub your eyes. This is the most common mistake we make because we feel a momentary sense of relief, but you can actually cause an eye injury.
• Wash your hands frequently. Do not touch your eyes with your hands unless you have just washed them, and use clean sheets and towels daily.
• Stop wearing contact lenses until symptoms improve or a specialist determines the cause of the red eye.

Some causes of red eye

• CONJUNCTIVIS: It is an inflammation of the conjunctiva and its blood vessels, which gives it that red or pink appearance. Conjunctivitis causes a foreign body sensation, but it is not painful and does not cause loss of vision.
• OCCULAR DRYNESS: This occurs when the eye does not produce enough tears or the tears are of poor quality and evaporate before properly hydrating the eye. This situation can cause inflammation of the surface of the eye, resulting in dry and red eyes.
• BLEPHARITIS: Inflammation around the edge of the eyelids causing redness and flaking. It does not usually cause permanent damage to vision and is not contagious.
• ALLERGY: Red eye can be a very clear symptom of allergy, because when the body’s defenses are confronted with an allergen, they release histamine as part of their defensive response. This histamine released by the body swells the blood vessels in the eyes and makes them red.
• COLDS: Red eyes are also a symptom of a cold or the flu.
• SCREENS : Working in front of a computer or tablet reduces the blinking of the eyes and, therefore, their hydration. When this happens, it is possible that eye redness combined with burning in the area and also tiredness may appear.
• KERATITIS: This is an inflammation of the cornea, the transparent front layer that protects the eye, and can become a serious situation. It has its origin in infections or trauma that have not been treated. It looks like a ring-shaped red eye around the cornea. It can cause pain and visual loss.
• EYE INJURY or CORNEAL ULCER: In response to an eye injury or wound, the blood vessels in the eye dilate as a healing measure and this is when the eye appears red. The causes can be many, for example, trauma, infection, extreme dryness of the eye and other eye disorders.
• CONTACT LENSES: They can be a cause of red eye due to a more prolonged use than stipulated or poor cleaning, as they can accumulate microorganisms and deposits.
• ANTERIOR SCLERITIS OR EPIESCLERITIS: It is an inflammation of the sclera (the white part of the eye). It may redden one part of the eye or be of a generalized type.
• UVEITIS: Red eye can also be caused by acute anterior uveitis. This is an inflammation of the uvea, the middle layer of the eye. It produces diffuse redness, but is often most intense around the cornea, in a ring-like shape. It manifests with pain and possibly vision problems (foreign bodies, blurred vision…) or visual loss.
• SUBCONJUNCTIVAL HEMORRHAGE: This is blood under the conjunctiva. It is a much more intense redness than the other pathologies described. It is not painful, nor does it present visual loss. It can have different degrees of intensity.
• PTERYGIUM AND PINGUECULA: These are conjunctival folds in the cornea that can be easily irritated. Although initially there is usually no danger and the usual treatment is lubrication, pterygium usually requires surgical treatment in cases where it is constantly red or invades the cornea and affects vision.
• ACUTE ENDOFTALMITIS: It is an infection of the inner part of the eye. There are two ways of contracting it: the first is that the infection is external and passes to the internal part of the eye after an eye operation. The second is through the blood, in case external organisms manage to enter the eye. If you have recently undergone surgery, it is important to go to the emergency room in case of any abnormality.
• OCCULAR HERPES: Occurs as a result of infection caused by the herpes virus. The main symptoms of ocular herpes are red eye, swelling, pain and a watery discharge accompanied by sensitivity to light.
• GLAUCOMA: Red eye can be a symptom of acute, that is, sudden onset, glaucoma. In addition to red eye, glaucoma also causes eye pain, loss of vision, nausea or halos around lights.
• SMOKING: Tobacco smoking is an eye irritant that causes red eye and increases the chances of macular degeneration, cataracts or uveitis. Marijuana use also produces the red eye effect because its main element, THC, dilates blood vessels.
• ENVIRONMENTAL CONDITIONS: A very dry environment in the workplace, long exposure to the sun or dust can generate eye redness.
• LITTLE SLEEP: Resting fewer hours than the body needs also affects the eyes and causes the red eye symptom.
• SWIMMING: The sanitizers used in swimming pools can also cause redness. If this is a common occurrence for you, the recommendation is to wear goggles to reduce the risk.

Frequently Asked Questions

How long does it take to heal red eyes?

The time will logically depend on the pathology that has caused it and the type of treatment given.

What should I do if my eye hurts and is red?

In situations in which these two symptoms are associated, it is advisable to go to the emergency room to be evaluated by a medical professional.

What should I do if I have a red spot in my eye, like an effusion?

Whenever there is an unusual symptom, in this case an effusion, although it is not usually serious, it is advisable to be evaluated by a specialist to rule out any pathology that may be serious.

What are the drops for red eye?

There are countless eye drops for red eye. In general, it would be advisable to use lubricant eye drops made of artificial tears without preservatives. Do not abuse eye drops promoted as decongestants because they can generate a rebound effect, that is, if they are used many times a day, they can cause more red eye. And it is not recommended to use steroid eye drops without being evaluated by a professional because the use of corticosteroids should be indicated in certain pathologies and avoided in others.

Can red eye be due to stress?

Stress directly should not cause red eye, but if stress causes behaviors that favor red eye (little sleep, many hours of screen time, smoking, etc.) this can cause red eye or prolong it over time.