Skip to main content

Acetylcysteine for dry eyes


Acetylcysteine eye drops act as artificial tears. They make dry eyes feel more comfortable.

Use the drops three or four times daily.

If your vision becomes blurred for a short while after using the drops, do not drive until you can see clearly again.

Continue reading below

About acetylcysteine eye drops

Type of medicine

Eye lubricant

Used for

Dry eyes

Also called


Available as

Eye drops

Acetylcysteine works by reducing the stickiness of tears. In the brand Ilube®, acetylcysteine is combined with an ingredient called hypromellose which soothes and lubricates the surface of your eye. These two ingredients together act as artificial tears. The drops ease eye dryness and soreness which is associated with some dry eye conditions, and make your eyes feel more comfortable.

Acetylcysteine eye drops are available on a prescription from a doctor.

Before using acetylcysteine eye drops

To make sure this is the right treatment for you, before you start using the eye drops it is important that your doctor knows:

  • If you wear soft contact lenses.

  • If you have ever had an allergic reaction to a preservative in eye drops.

  • If you are pregnant or breastfeeding.

Continue reading below

How to use acetylcysteine (Ilube®) eye drops

  1. Wash your hands before you use the drops.

  2. Remove the yellow plastic disc, the metal ring and the black rubber bung from the top of the bottle of eye drops. Next, take the plastic dropper from the packet and gently, but firmly, push it on to the top of the opened bottle.

  3. Remove the plastic cap from the dropper.

  4. Tilt your head back a little and pull the lower lid of your eye downwards to form a pocket.

  5. Hold the bottle upside down with the dropper near to your eye. Try not to touch your eye as you do this.

  6. Gently press the middle of the dropper to release one drop. Use a second drop if the first drop missed going into your eye.

  7. Close your eye for a minute or two, and press gently on the side of your nose where the corner of your eye meets your nose. This helps to stop the drop from draining away and keeps it in your eye.

  8. Repeat the process in your other eye if you have been told to use the drops in both eyes.

  9. Replace the plastic cap to protect the dropper.

Getting the most from your treatment

  • Before you start using the eye drops, read the manufacturer's printed information leaflet supplied with the pack. It will give you more information about using the drops and will provide you with a full list of any side-effects which you may experience.

  • Use one drop into the eye (or eyes) affected by dryness. You can do this three or four times each day unless you have been told otherwise by your doctor.

  • Please take care that the dropper doesn't touch your eye, your fingers, or any other surface. This could contaminate the drops left in the bottle.

  • If you forget to use the drops at your 'usual' time, do not worry, just put them in when you remember. Do not 'double up' the number of drops you use to make up for forgetting to use them.

  • When first put in, eye drops can cause blurred vision. This should quickly clear. Make sure you can see clearly again before you drive, or before you use tools or machines.

  • If you are using any other eye drops or ointments, leave about ten minutes between applying each one. It is usually recommended that you use the acetylcysteine drops last. This is so that the drops stay in contact with your eye and lubricate it for as long as possible.

  • If you wear soft contact lenses, remove them before applying the drops and wait at least 15 minutes before putting them back in. This is because the preservative used in the eye drops can affect soft contact lenses.

  • If your symptoms do not improve within a few days, make another appointment to see your doctor for advice.

Continue reading below

Can acetylcysteine eye drops cause problems?

The eye drops can occasionally cause mild eye irritation or redness, but these usually soon pass and not everyone will experience them. The preservative benzalkonium chloride can cause eye irritation and symptoms of dry eye. If eye irritation continues, or if you experience any other eye problems, speak with your doctor or pharmacist for advice.

How to store acetylcysteine eye drops

  • Keep all medicines out of the reach and sight of children.

  • Store in a cool, dry place, away from direct heat and light.

  • Ilube® eye drops only keep for four weeks once the bottle has been opened, so do not use these drops if the bottle has been open for longer than this. This helps to prevent the risk of eye infection.

Important information about all medicines

Important information about all medicines

Make sure that the person supplying this medicine knows about any other medicines that you are taking or using. This includes any medicines you have bought, and herbal and homeopathic medicines.

If you are having an operation or dental treatment, tell the person carrying out the treatment which medicines you are using.

This medicine is for you. Never give it to other people even if their condition appears to be the same as yours.

If you suspect that someone might have swallowed some of this medicine, contact your local accident and emergency department for advice.

Do not keep out-of-date or unwanted medicines. Take them to your local pharmacy which will dispose of them for you.

If you have any questions about this medicine ask your pharmacist.

MHRA - Reporting adverse reactions

Report suspected side effects to medicines, vaccines, e-cigarettes, medical device incidents, defective or falsified (fake) products to the Medicines and Healthcare products Regulatory Agency to ensure safe and effective use.

Further reading and references

Article history

The information on this page is written and peer reviewed by qualified clinicians.

symptom checker

Feeling unwell?

Assess your symptoms online for free