Most people at some point in their lives will experience an unpleasant but usually mild condition known as pink eye, or conjunctivitis. It typically starts as a burning, gritty, or itchy sensation, accompanied by some sort of unsightly discharge, and – as you would expect – the whites of the eye turn pink. An estimated 6 million Americans are affected by conjunctivitis every year with the annual cost of treating bacterial conjunctivitis predicted to be as high as $857 million.

What is pink eye?
At a basic level, conjunctivitis is any sort of inflammation of the mucosal membrane over the whites of the eye known as the conjunctiva. The types of conjunctivitis are as many as there are shades of pink – adenoviral conjunctivitis, bacterial conjunctivitis, allergic conjunctivitis, and chlamydial conjunctivitis are just a few. All types of infective conjunctivitis, whether viral or bacterial, are highly contagious and need to be avoided like cooties.

Common Causes of Pink Eye
The most common cause of conjunctivitis is a viral infection, which in most cases is not treatable and just needs time to burn itself out. Often, cases of viral conjunctivitis will be accompanied by a cold or some other upper respiratory tract infection.

Bacterial conjunctivitis is also fairly common and can usually be treated quite easily with antibacterial eyedrops or ointment. Contact lens wearers are at risk of more severe eye infections due to the nature of sticking a foreign object in the eye for several hours a day and so will usually require more potent antibiotics and closer monitoring. One way to help discriminate bacterial from viral conjunctivitis is that the gunk in bacterial pink eye tends to be more of a pus or mucous consistency (sounds delightful, doesn’t it), whereas viral conjunctivitis discharge is more watery.

Allergic conjunctivitis is an immune response to allergens in the environment, such as pollen or dust. This can happen seasonally, such as when pollen count is high in spring, or perennially, which means the poor person is tormented all year round from a constantly present allergen such as dust mites. Allergic conjunctivitis is typically hallmarked by intense itching and can be treated with anti-allergy eye drops or oral antihistamine medications.

What to Do If You Think You Have Pink Eye
First of all, keep calm.

Secondly, see an eye care professional for a proper diagnosis of pink eye. In addition to there being many causes of conjunctivitis, there are also many causes of a pink eye that are not conjunctivitis and some of these can be sight-threatening if not treated properly.

Viral conjunctivitis is typically self-resolving over a couple of weeks. In the meantime, supportive therapy such as cold packs or tear lubricants can help to alleviate discomfort. Keep up with impeccable hygiene – don’t share towels or washcloths, change your pillow case, discard any eye makeup, and avoid touching your eyes.

Some cases of conjunctivitis are caused by irritation from a foreign particle lodged somewhere in the eye. No matter how many eyedrops you squirt in there, the conjunctivitis will not resolve while the particle remains. Therefore, proper assessment by an eye care professional is important.

Can Babies Get Pink Eye?
Can they ever! Babies are great breeding grounds for disease, didn’t you know? Jokes aside, neonatal conjunctivitis, or ophthalmia neonatorum, is a real problem as scarring of the ocular tissues can lead to permanent blindness. Chlamydial infection from an untreated infected mother has a 30-40% chance of being transferred to the baby as it passes through the birth canal and can result in a nasty conjunctivitis. Gonococcal conjunctivitis is even more fearsome and requires very prompt diagnosis and treatment to avoid irreversible loss of vision or potentially fatal systemic infection. Treatment of neonatal conjunctivitis usually involves topical antibiotic eye drops or ointments but also systemic intravenous antibiotics.

Up to the age of 12 months, it is not uncommon for a baby’s tear ducts to not yet be fully open or to become blocked. This can cause a newborn to become more prone to conjunctivitis though sometimes watering from the eye can simply be from tears that are unable to drain down the usual channels. Apparently, babies tend to cry a lot. If the tear duct remains unopened past the age of one year, a surgical procedure can be performed.

References
Pink eye (conjunctivitis). https://www.mayoclinic.org/diseases-conditions/pink-eye/symptoms-causes/syc-20376355
Facts about pink eye. https://nei.nih.gov/health/pinkeye/pink_facts
Neonatal conjunctivitis. http://eyewiki.aao.org/Neonatal_Conjunctivitis
Conjunctivitis: a systemic review of diagnosis and treatment. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4049531/