En español | You know it when you see it. Conjunctivitis (more commonly known by the more colorful moniker pink eye) happens when the conjunctiva — the thin, clear tissue lining the inner surface of the eyelid and covering the white part of your eye — becomes inflamed. Eyes become reddish and itchy, with swollen, crusty lids, and sometimes a watery or sticky discharge.
Pink eye is usually caused by a virus, and can be very contagious. You can catch it when someone with an upper respiratory infection sneezes or coughs in your direction, or when a virus hitches a ride on your mucous membranes and travels from your nose to your eye.
Less common: bacterial conjunctivitis, an infection caused by bacteria living on your own skin. Contamination — say, touching your eyes with dirty hands, sharing a towel with the wrong person, or applying eye makeup past its expiration date — can bring on a nasty bout.
A 2017 University of Michigan study found that about 60 percent of patients are prescribed antibiotic eye drops, even though they are usually unnecessary. Of those patients, 20 percent have prescriptions filled for antibiotic-steroid eye drops that could potentially prolong or even worsen the infection. What's behind the blunder: “Pink eye is often diagnosed and treated by a primary care physician or urgent care provider, rather than an ophthalmologist,” says Michelle Andreoli, a Wheaton, Illinois-based ophthalmologist and spokesperson for the American Academy of Ophthalmology. “They may not be able to differentiate between conjunctivitis that's bacterial or viral, and prescribe a topical antibiotic. However, viral conjunctivitis doesn't respond to antibiotics.”
The good news is that in most cases of viral conjunctivitis, without any treatment, in a week or two your body recovers from whatever infection it had. A mild case of bacterial conjunctivitis may also get better without antibiotics, though medicated eye drops may be prescribed in some cases.
To ease discomfort until the condition runs its course, use artificial tears to help with itching, irritation and redness. Wash the area two to three times a day, using a cool, wet washcloth to wipe away any discharge — and resist the urge to rub. Cold packs can help with swelling. Clean your glasses regularly and ask your eye doctor about how to deal with your contact lenses. Toss eye makeup (mascara and eyeliner, in particular, are potent breeding grounds for bacteria), and don't share personal items (pillows, towels, makeup) with others.
Keep in mind, warns Andreoli, some viruses can cause a relapsing conjunctivitis for up to a year, which can lead to scarring of the cornea and even vision loss. “People think they have a little benign pink eye, get some drops, and things are kind of quiet for a couple of weeks — then lo and behold, their eyes turn red again,” she says.
See a doctor if you're experiencing pain, you notice a lot of mucus, your vision becomes blurry or sensitive to light, or symptoms don't get better.
Another cause of pink eye: allergic conjunctivitis
We know that allergies can do a number on our breathing, but they can also aggravate our eyes. Blame an overeager immune system that overreacts to harmless substances and releases histamine, causing redness, itchiness, swelling and watery discharge. Among the things that can trigger a reaction: household dust, pollen, animal dander, mold, and chemical scents found in household detergents and perfume.
Get relief by washing your eyes and lashes twice a day, in the morning and before bed, using a mild face soap, to rinse whatever it is that you're allergic to off your face and skin. “Pollen, for example, sticks to your lashes, and if you don't scrub that away it can chronically irritate your eyes,” says Andreoli. Avoid allergens that are making your eyes miserable. Keep the house dust-free or use an indoor air purifier. Stay inside as much as possible during pollen-heavy days and slip on sunglasses when outdoors so airborne allergens can't cling to your lashes or contacts. And be sure to keep pillowcases clean.
For mild symptoms, incorporate over-the-counter artificial teardrops into your daily arsenal. “They act as windshield wipers for the surface of your eyes,” says Andreoli. “Put a drop into your eyes, blink, and the solution will sweep the schmutz that's sitting on the surface into the tear drain, taking the allergen with it.” Look for products that are preservative-free. If you have allergic conjunctivitis, your eyes are sensitive in general, so staying away from anything that can increase that sensitivity is important.
Antihistamines, which reduce allergic reactions, can be used systemically for treating allergy symptoms, eyelid swelling included. “There are also drops you can use to target the eyes specifically, which contain antihistamines as well as mast cell stabilizers that prevent the release of histamines,” says John Ng, a professor of ophthalmology and an orbital trauma specialist at Oregon Health & Science University in Portland. Anti-inflammatory or steroid eye drops may be used when other therapies have failed, but because of possible side effects, such as cataracts and glaucoma, they aren't recommended for long-term use.