Are you overusing your over-the-counter red eye drops? |15 November 2023

There is a variety of eye drops that can be bought from pharmacies with or without a prescription. It is very important that they are used correctly, effectively and for the duration of time advised by the medical professional.

Eye drops are used to treat eye conditions such as dry eyes, eye allergies, eye infections and glaucoma (increase in pressure of the eye which can damage the optic nerve). Eye drops are usually very effective if used correctly. However, some patients do tend to overuse them which in turn increases the risk of adverse effects and in some cases, may cause other eye problems to develop.

Probably the most common over-used eye drops in Seychelles are those used for red eyes. Some drops used for red eyes that can be bought over the counter from pharmacies contain ingredients known as decongestants: xylometazoline, oxymetazoline, phenylephrine, tetrahydrozoline or naphazoline. While effective in clearing up the condition, overuse of these ingredients can cause a dependency, known medically as a ‘rebound effect’.

What is a rebound effect?

Many things can contribute to red eyes. Examples include:

o    Dust

o    Allergies

o    Staring at a screen for long hours

o    Lack of sleep

o    Alcohol

o    Drugs

When something irritates the eye, the blood vessels in the white part of the eye, the sclera, become swollen (dilated). This causes the red colour. Eye drops used to treat this condition work by making these blood vessels smaller (constriction) and so the amount of blood flowing through them reduces. This causes the red colour to subside.

When used correctly and for short periods of time, such eye drops are very effective and don’t usually cause any problems. However, there are some patients who tend to overuse these drops. What they don’t realise, though, is that overuse of these drops will cause them to actually do the opposite of what they are supposed to do! Constantly putting the same drops in your eyes will cause the blood vessels to remain small (constricted). Your eyes then need to work harder to push nutrients and oxygen through these small vessels. Your body tries to compensate for this by forcing open (dilating) the vessels thus causing the swelling and redness to start again. This is what we call a rebound effect.

It is also important to note that overuse of eye drops used to treat red eyes could actually mask a more serious, underlying medical problem like inflammation, infection or trauma. If these problems remain untreated it could lead to permanent damage to your eyes or vision.

How can you break the cycle of rebound effects?

Dealing with the cause of the redness is the main way to reduce the need for eye drops and therefore the risk of developing rebound effects. Some things that may help include using preservative-free lubricating eye drops or eye gels, and applying a cool or warm compress over your eyes during the day.

If the redness persists or if there is any pain, it is highly recommended that you see your eye doctor.

Always ask your pharmacist for any medical advice. That’s what we are here for.

Written by: Zarine Durup – Pharmacist at Behram’s Plaisance Pharmacy (on behalf of the forthcoming Seychelles Pharmacy Association)