A “red eye” is a term to represent eyes that are irritated and bloodshot. When tiny blood vessels under the eye’s surface are enlarged or become inflamed in response to an irritant, our eyes become red. The condition can progress over time or surface abruptly, and might affect one or both eyes. Typically, red eyes happen together with itching, eye pain, discharge, swollen eyes, and/or vision changes.
What are the causes of red eyes?
Red eyes have several causes, such as:
When an irritant (such as dust, pollen or chemicals contained in eye makeup) enters your body, it triggers a reaction in the immune system. Your body releases histamine to combat the irritants, causing the blood vessels in your eyes to enlarge, Hence, your eyes become red and itchy.
- Blepharitis (inflamed eyelid)
Blepharitis is an inflammation of the eyelids and eyelid margins. Besides a red and/or swollen eyelid, your eye might tear excessively, be sensitive to light and/or you may experience a burning sensation
- Conjunctivitis (pink eye)
Conjunctivitis happens due to an inflammation of the conjunctiva (thin, transparent membrane that envelops the white part of your eye and lines your eyelids). Subsequently, the blood vessels inside the conjunctiva swell, causing your eye to appear red or pink. Also, your eyelids might also release a sticky discharge.
- Dry eye
Dry eyes happen when your eyes do not produce enough tears which are important in maintaining hydration of your eyes and keeping the surface of the eye healthy. Dry eyes may cause red eyes and a stinging or burning sensation.
- Eye injury
Eye injuries can lead to red and bloodshot eyes. This is because blood vessels in the eye dilate (widen) for more blood to arrive at the injured area for faster recovery. These open blood vessels give rise to the appearance of the condition.
Acute glaucoma is a sight-threatening condition that needs urgent medical attention. Its symptoms include abruptly painful, red eyes, accompanied by vision loss, seeing halos around lights, and nausea.
Eye diseases are not the only cause of red eyes. There are other causes of the condition, such as:
- Excessive alcohol consumption
Too much alcohol consumption decreases oxygen to red blood cells. Thus blood vessels clump together and eyes look bloodshot.
Tobacco smoke can lead to dry, red, and itchy eyes. Smoking marijuana also causes red, bloodshot eyes as an ingredient in marijuana causes the blood vessels in the eye to dilate. Hence, your eyes can become red for a couple of hours.
- Skin products or cosmetics
Facial or eye products may contain chemicals that irritate the eyes, causing redness.
What are the treatments for red eyes?
There are various treatments for the condition, depending on the cause of the condition.
- If caused by allergies
In addition to avoiding the allergen (if it is known), treatment includes over-the-counter eye drops such as artificial tears and eye lubricants. Eye drops will remove allergens from the eye and give moisture to irritated eyes. Moreover, decongestant or antihistamine eye drops reduce redness in the eyes from allergies and can help relieve itchiness.
For the treatment of blepharitis, the eyelids should be cleaned regularly to wash off any dandruff, bacteria, and build-up of debris around the eyelashes. This can be done by using over-the-counter lid cleaning products applied to the lash margins with a swab or cotton bud. If a dedicated eyelid cleaner is not available, a mixture of water and baby shampoo can also be used. Your doctor may also prescribe antibiotics or steroid eye drops to calm the inflammation and treat infection, if any.
- Bacterial or viral pink eye
First, put a clean and damp washcloth over the closed eye for a few minutes to loosen dried mucus if eyelashes or eyelids are stuck together. Make sure to use a different washcloth for each infected eye to avoid cross-contamination. Use over-the-counter eye drops such as artificial tears or eye lubricants to alleviate the discomfort.
If symptoms persist despite trying the above-mentioned first-line treatments or if vision is affected, schedule an appointment with an ophthalmologist (eye doctor) using planoEyecheck.
Cleveland Clinic. 2021. Red Eye: Causes, Symptoms, Treatments, Prevention. [online] Available at: <https://my.clevelandclinic.org/health/symptoms/17690-red-eye> [Accessed 15 December 2021].