Recently, just as I thought I was turning the corner on dealing with my own upper respiratory infection, one of the eyes looking back at me from the mirror was red with some thick crusty stuff in and around it (affectionately termed “eye boogers” by many).  I had that common malady which goes by a variety of names such as conjunctivitis, pink eye, or red eye.  This is an inflammation or infection of the conjunctiva which is the thin clear tissue covering the white part of the eye and the inside of the eyelid.  When it gets inflamed it turns pink or reddish.

So what causes conjunctivitis?  The big three are bacterial, viral and allergic.  The first two of these are infectious and are about equal in frequency.  Bacterial conjunctivitis tends to look a bit more angry and red and to have a thicker discharge, sometimes leaving the lids pasted shut in the morning.  Viral conjunctivitis tends to have a more watery discharge, but there is a lot of overlap of signs and symptoms between these two types of conjunctivitis.

The main practical difference is that bacterial responds well to antibiotic drops while viral does not, needing to just run its course.  By the way, with my recent case of bacterial conjunctivitis I was reminded how challenging the simple job of putting drops in your own eyes can be.  My eyelashes and cheeks were more likely to be watered by my eye drops than the actual eye.  At any rate, both of these types of conjunctivitis are quite contagious.  So if you have either one in one eye it is vital to not rub that eye and then the other or wipe a towel or wash cloth from one to the other as it will spread the infection to the unaffected eye.  Even more important is to not share towels or wash cloths with uninfected family members while you have conjunctivitis.  Likewise, rubbing your eyes leaves your hand with infectious material that can then be spread to others.

This is why most daycares and schools encourage children with conjunctivitis to be kept home until symptoms have cleared.  Unfortunately, in the case of viral conjunctivitis, that can be up to 1-2 weeks in some cases.  Bacterial conjunctivitis is usually considered non-contagious after 24 hours of antibiotic drops.

Although these kinds of conjunctivitis are usually not dangerous, there are a couple of special cases that are more worrisome.  In newborns, any conjunctivitis should be checked out quickly and treated aggressively as there are some sight-threatening infections that occur in the newborn period.  That’s why states, including Tennessee, mandate an antibiotic eye ointment for all newborns. Other types of conjunctivitis, which are more serious but also more rare, include herpes, gonorrhea and chlamydia.  All require aggressive, specific treatments to clear them up and prevent eye damage.

Allergic conjunctivitis looks similar to viral, with watery discharge, pink color and itching.  It tends to persist through an allergy season and responds to oral allergy meds and allergy eye drops.  It is, of course, non-contagious but can worry teachers and daycare overseers if they think it is one of the contagious types of pink eye.

Another tricky thing about a pink or red eye is that it is not always conjunctivitis.  Similar symptoms can be caused by getting something in the eye (foreign body, chemical, or other irritant).  This is particularly likely if only one eye is affected.   Other conditions such as glaucoma or inflammations of other structures in the eye (iritis, uveitis) are also causes of a pink or red eye.

So if you wake up to that not-so-pretty color of pink in your eye, or a bunch of eye boogers, given the varied causes and repercussions, it’s a good idea to let your doc have a look.