C.R. Williams
19th Sep

That Looks a Bit Sore: Eye Redness Symptoms and Causes

Red eyes come in many forms and for many reasons. Most of the time people just take a guess to what the cause could be and consequently how they should treat it. Mistreating the problem usually means the problem just doesn’t go away. Occasionally the wrong treatment can lead to a worsening of what could be a damaging condition.

Rule number one has to be: if you’re not sure - get advice. And if you are looking for advice, go to an expert - an Optometrist.

More often than not a GP appointment will not be available for several days, if not a week. A Pharmacist may not want to be too specific about passing an opinion. Neither is likely to have the equipment to be able to examine the eyes in detail.

Your Optometrist will seek to find out the background information to the red eye. Is it one eye or two? What is the nature of any discharge from the eye? Has the vision been affected? What is the discomfort level like? How long has the condition lasted and when is it at its worst?

Dry Eye

The most common cause of red eye is poor tear quality - a dry eye. Dry eye can be caused by a naturally poor tear quality, an eyelid inflammation, or can be self-inflicted (overtiredness, too much computer use, heavy night last night, etc). See my previous blog about dry eyes.


Allergies play a big role in eye discomfort. Where possible, the cause rather than the red eye should be tackled, but as hay fever sufferers will tell you - that is not always easy. If you know you are due an allergic episode as spring approaches, start your treatment early and keep it up. It takes a while for the medication to kick in and protect you. If you only start taking them once you are suffering, you’ll have an upward battle to get on top of it.


Conjunctivitis will cause sticky, sore, light-sensitive eyes. The first thing people often do is reach for the antibiotics. The problem is that if the infection is not caused by bacteria, then the medication will not work.  Over use of antibiotics is arguably becoming a problem. It is also worth bearing in mind that with regular cleansing, the bacterial infection sorts itself out in a couple of weeks.

Viral conjunctivitis is quite different and may need very specialist treatment. Left untreated, or being incorrectly treated, could be sight threatening.

Broken Blood Vessels

Broken blood vessels on the white of the eye are very common and rarely pose any threat to the eye itself. In general, the eye just has to be left alone to reabsorb the blood over the next week or so.

However, sometimes it’s worth finding out if there is a background cause, such as poorly controlled blood pressure.

More serious eye conditions

There are also various eye specific problems that can give a red eye appearance, such as acute glaucoma, iritis and corneal ulcers that need prompt action. Only a detailed examination of the eye will be able to detect the nature of the cause and hence the right course of treatment.

If you have any concerns about your eyes - ask an eye expert.  An optometrist may charge you for their time, but you can’t really put a value on your eyesight and your peace of mind.

Back to list