Why Are My Eyes Red?

My residency program director said there are over a hundred reasons for red eyes. I never sat down to count, but I’d guess he was probably correct. So first and foremost: get an eye exam to rule out serious, vision-threatening problems. I have seen patients many times in my career who had viral infections, deep inflammation called uveitis, and other serious eye conditions that they underestimated as harmless red eyes. So PLEASE get a comprehensive eye exam first to make sure it’s not a progressive, vision-threatening eye condition. Furthermore, redness of the eyes is virtually always some sort of inflammation, and inflammation is never good for you in the long run.

All redness of the eyes is due to the dilation of the blood vessels in the sclera (the white part of the eyes) and the conjunctiva (the clear mucous membranes covering the white of the eyes). The dilation of these fine blood vessels allows more blood to flow through the surface of the eyes and gives the appearance of redness. The vast majority of red eyes are probably due to three causes: allergic conjunctivitis, dry eyes, and meibomian gland dysfunction. I’ll discuss each of these three conditions, and list two more to round out the top five causes of red eyes.

Conjunctivitis

First, and arguably the most common cause of red eyes is allergic conjunctivitis. I always recommend finding out exactly what is causing the problem by getting tested by an allergist. You’d be surprised what odd things may be causing you to suffer. Allergic to Birch bark, anyone? Allergies can be year-round, caused by constant exposure to the offending agents in your house such as dust, mold, pet dander or pet saliva-or contact lenses! Many times I’ve seen young people who think their eyes are dry with contacts, when they’re actually allergic to them (see Giant Papillary Conjunctivitis below) A pro tip: if your upper eyelids itch, take a look at your fingernails. Are they painted? The metals in nail polish are the most likely cause. Remove it – pronto!

Fixing Allergy-Induced Red Eyes

Seasonal allergies have predictable periods due to the pollens of flowering plants. Avoiding these is usually not totally possible, but air filters both in central heating/air conditioning or stand-alone can help. Don’t forget to change the filters frequently. Hand washing, clothes washing, and staying indoors can reduce one’s exposure. There are many OTC medications that may help, although you may have to try multiple different categories and types to find what works best for you. There are several eye drops, both by prescription and OTC that may help. My favorite, Pataday (Olopatadine) eye drops were approved for over the counter in February of 2020, which is a great thing for allergy sufferers.

Dry Eyes – And How to Fix Them

The second most common cause of red eyes is dryness. This condition is super prevalent, and is much more common in women than men, and increases with age. After menopause, it is highly prevalent and can become debilitating. There are dozens of different therapies to treat dryness, but no magic bullet. I always start with just artificial tears, which are easy to use, give instant relief, zero risk, and can be used only when needed. If that alone doesn’t give adequate relief, my recommendation to my patients depends on the patient’s age, symptoms and signs. A majority of people with dry eye syndrome (isn’t everything a syndrome these days?) experience dryness upon awakening, and can benefit from nighttime use of ophthalmic lubricating gel or ointment such as Lacrilube or Duratears. The formulation of these is the same as Vaseline, but comes in a small tube. Pro tip: run the tube under hot tap water for 20 seconds to liquefy it, and use the smallest amount possible. It’s messy, and less is more.

Alternatives to ointment are myriad. There are prescription eye drops, that have been on the market called Restasis and now Xiidra for a long time. I’ve always been underwhelmed by the feedback from my patients using these. They take weeks to months to have an effect, can burn or taste bad after instillation, and they’re super expensive! Xiidra is $550 per Goodrx.com on March 10, 2020.  and Restasis is $581. They’d better work some magic at that price, and I’ve never seen magic, so I always say don’t get it unless you only have a low copay. Punctal plugs are fairly effective, small, innocuous devices that can stop the flow of tears into the tiny duct in the inner corner of your eye that you may not know you had. They can be temporary, and dissolvable, or “permanent” (until they fall out) silicone or other materials. Most people don’t feel them, and benefit, but they often fall out over time.

If dryness isn’t helped by any of the above, a dry eye specialist may need to assess and treat you. It’s important to good vision and comfort that the surface of your eyes is healthy and lubricated. (More than) enough on that!

Eyelids

Another common cause of redness of the eyes is due to your eyelids. There are about 25 oil glands in each of our upper and lower eyelids that are called Meibomian glands. When they get plugged, they don’t secrete oil onto the surface of the eye. This is called Meibomian Gland Dysfunction, and can contribute to dryness. It’s often what causes that “red-rimmed” look to the eyes. A “Stye” can develop, which is analogous to a pimple on the skin, whereby the blocked gland causes inflammation, swelling and redness on the eyelid that can be tender and unsightly. There are several new treatments for this condition that are seemingly working. Lipiflow is the best known, but this area of therapy is growing.

Other Possible Sources

Two more conditions that often cause dryness of the eyes: contact lenses and (temporarily) LASIK and PRK. If you can’t comfortably wear contacts, LASIK can be a great option. Laser vision correction in my experience causes probably nine of ten patients to have dry eye symptoms in the first month. It’s more prevalent in women and older people (50+ years old). It typically lasts more than a month, but does get back to baseline. If you have dryness before LASIK, you will most likely have the same dryness long term afterward. For contact lens wearers, LASIK often makes eyes feel better long term, because the contacts aren’t bothering them. Especially in people with a condition called “Giant Papillary Conjunctivitis, which is an allergy to the contacts themselves, and can be misdiagnosed as dry eyes. Your eye doctor will “flip” or evert your eyelids to confirm this diagnosis.

Now, How Do I Fix My Red Eyes?

So you’ve read or skipped down to here. Once you’ve made sure that there’s nothing seriously wrong with your eyes, there’s a great new medication called Lumify. We’ve been using the active ingredient in Lumify, Brimonidine Tartrate for decades for glaucoma treatment. I always knew it was a potent vasoconstrictor, or shrank the blood vessels in the eye and made them extremely white. My friend Gerry Horn, MD had the good sense to formulate it and it is now available at all pharmacies over-the-counter. It’s at a lower concentration than the glaucoma drop, so while it still works beautifully for whitening the eyes, it has fewer side effects. Check it out here.

– Dr. Matthew Sharpe MD