Tell me about... Sore eyes and conjunctivitis

I recently had a 'sore eye'. People at work asked me to go see a doctor. I went to one, and he said that I had conjunctivitis. What is this?

The term "sore eye" is used quite often in Malaysia for conjunctivitis. But in the United States, they call it "pink eye", because sore eye is used for other conditions.

In the US, the term sore eye denotes any red, irritated, or bloodshot eye. This can be due to bleeding under the conjunctiva, inflamed eyelids, or a stye (a bump on the eyelid).

Sometimes, sore eye is also used for that photo flash effect when your picture is taken in semi-darkness, and your eyes appear red in the captured shot.

Now let's go to pink eye. This is what happens when the transparent membrane that lines the eyes becomes infected or inflamed. This membrane is called the conjunctiva.

The pinkness is caused by the dilatation of the small blood vessels in the conjunctiva. So now the whites of the eyes appear reddish or pink.

What is the conjunctiva for?

The conjunctiva is a thin, semi-transparent membrane. It is made out of epithelial cells and lines the white part of the eye. This lining is important because the conjunctiva helps prevent the entrance of microorganisms into our eyes.

Other than protection, the conjunctiva produces mucous and tears to lubricate the eye. Yes, this is different from the tears produced by the lacrimal glands or tear ducts. The tears produced by the conjunctiva are of smaller volume.

Many people don't realise this, but the conjunctiva also goes beyond the white part of the eye (sclera) that you can see. It also lines the insides of the eyelids.

The conjunctiva may appear transparent, but it is actually supplied by blood vessels and nerves.

The conjunctiva is arranged in the eye in such a way to allow movement of the eyeballs within their sockets.

What causes conjunctivitis?

Most people think it's just infection, but no, there are also other reasons. When you get pink eye, it can be due to:

Virus and bacteria: This may affect one or both eyes. A virus usually produces a watery discharge while bacteria produce a thicker, yellow-green discharge.

Both viral and bacterial conjunctivitis are very contagious. Stay away from your colleagues and loved ones. Conjunctivitis can be spread by direct contact or through the eye secretions.

Sometimes, it is associated with other cough or cold symptoms.

Allergies: This type of conjunctivitis affects both eyes. It is caused by an immune response to things you may be allergic to, such as pollen.

This type of conjunctivitis is pure inflammation, and can be very itchy. It can also be accompanied by a lot of tearing and sneezing.

Irritation: When you get a foreign object or chemical in your eye, this can cause irritation. People who misuse contact lenses get this a lot.

You can flush your eye to get rid of the object. This usually clears up within a day or two.

Is conjunctivitis painful?

More often than not, it is irritating rather than painful.

In conjunctivitis, the eye is red or pink, itchy, gritty and has a discharge. This discharge may form a crust during the night when you sleep.

In the morning, you will then have a crust that prevents your eyes from opening easily until you clear it up.

Your eyes can also produce a lot of tears during conjunctivitis.

Should I see a doctor or will this clear away by itself?

You should see a doctor and stay away from other people.

Conjunctivitis can be contagious for up to two weeks. If you are wearing contact lenses, take them out immediately and stop wearing them until one week after your symptoms have cleared.

Conjunctivitis is not a serious condition, right? It won't cause blindness or anything? I'm a contact lens wearer.

Conjunctivitis itself is not that serious if it's just limited to the conjunctiva. The trouble is if the infection spreads to the cornea, which covers the pupil of your eye.

Once the cornea is infected, this can cause vision problems. It is best to go to a doctor and have it diagnosed and treated properly.

Dr YLM graduated as a medical doctor, and has been writing for many years on various subjects such as medicine, health, computers and entertainment. For further information, e-mail starhealth@thestar.com.my. The information contained in this column is for general educational purposes only. Neither The Star nor the author gives any warranty on accuracy, completeness, functionality, usefulness or other assurances as to such information. The Star and the author disclaim all responsibility for any losses, damage to property or personal injury suffered directly or indirectly from reliance on such information.