¡®Red eye¡¯ is a term used when the eye is red, itchy, watery and feels gritty. It may be caused by an infection, an allergy such as hayfever or an irritation such as smoke, dust, eye make-up, or computer screens. When an infection causes the eye to look red, there is usually a thicker discharge and a ¡®gritty¡¯ feeling in the eye.

An allergy results in bloodshot, glazed eyes that are watery and very itchy. The surrounding area may be puffy or there may be dark circles under the eyes.

¡®Dry eye¡¯, which is common in the elderly and may be caused by some medicines, may also redden the eyes but requires different treatment to ¡®red eye¡¯.

When should you seek medical advice?
You should seek medical advice if:

• the discharge from your eye is thick;
• your eyelids are stuck together on waking;
• you have a change in vision, or your vision is blurred;
• there is a foreign object in your eye;
• you have been working with metal shavings or wood turning;
• you see a halo effect around lights;
• your pupils are different sizes;
• there is swelling around your eye or the lower lid;
• you experience pain or a feeling of tension in or around your eyes;
• the ¡®red eye¡¯ has lasted more than 5-7 days;
• there is a coexisting eye problem such as glaucoma, or ¡®dry eye¡¯ in the elderly; or
• you have ¡®tired¡¯ eyes, but do not have the accompanying signs of ¡®red eye¡¯ (this could be eye strain and requires eye tests).

What can you do to help?
You should try to avoid substances that irritate your eyes, such as smoke, dust, cosmetics and chlorine in swimming pools, if these are known aggravating factors.

You should also remove your contact lenses before using some types of eye drops, and should not wear contact lenses at all if an eye infection is present. Some drops contain medicines or preservatives that will damage contact lenses.

You should also discard all drops, solutions and ointments one month after opening. However, unit dose lubricant eye drop packs remain sterile until opened, if used within the expiry date printed on the packet.