All About Eye Drops

Glaucoma, eye pressure and eye drops

Eye drops are the most common treatment for glaucoma. They decrease the amount of fluid in the eye, either by increasing the drainage of fluid out of the eye or by reducing the amount of fluid that is made. The build-up of fluid in the eye is called aqueous humour, or just aqueous. This fluid causes pressure in the eye (called intraocular pressure or IOP) to increase, which damages the optic nerve and leads to vision loss

There are lots of different eye drops that can be used to treat glaucoma. They all work in different ways, but they all have a role to play in reducing the amount of fluid in your eye to reduce intraocular pressure ( IOP) and reduce damage to the optic nerve.

How to Put in Eye Drops

There are many kinds of eye drops, and any of them could be a challenge to get into your eye. But with a few tips and some practice, you’ll get more comfortable with the process. The more familiar and confident you are, the easier it will be to put in eye drops without missing, spilling or using too much.

Eye Drop Supports

Frequently asked questions about eye drops

Why are eye drops used in glaucoma?

The answer is to help prevent the loss of vision from glaucoma. The exact cause of glaucoma is not known, but we know age, family history and raised pressure in the eyes (intraocular pressure) are risk factors. Of these, only the eye pressure is modifiable, and lowering it slows the loss of peripheral, and then central, vision in glaucoma.

Eye drops are the most common and preferred way of achieving this.

Why do I have to use my eye drops permanently and continually?

In order to prevent visual loss the pressure must be constantly controlled. The effect of each dose of drops lasts for only a limited time.

If a drop is given four times a day, it is because the effect of the drop only lasts about 6 hours. If the drops are not continuously used the pressure will creep back up again.

Do I have to get up at night to take my eye drops?

You should not need to get up at night for eye drops. An undisturbed night is more important, but if prescribed for use three or more times daily, it is usually desirable to put them in last thing at night and as soon as you wake up in the morning.

Are my eye drops supposed to sting when I put them in?

All drops may cause some burning or stinging when instilled. Often, this effect is due not to the drug but to the antibacterial preservatives in the solution.

It is rarely intolerable and can be used to advantage since it lets the patient know that the drop got into the eye. If you are experiencing a lot of discomfort you should report this to your eye specialist, as there may be different options for you.

If I have two lots of drops due at the same time, can I put them in together?

It is probably best to allow five minutes between drops to avoid one drop washing out the previous one. Ask your eye specialist for specific advice about the drops you are taking.

Do I need to put the drops in before I come to the clinic?

Always continue as usual unless requested otherwise. It helps the doctor to judge the effect of the treatment.

Does it matter if I put more drops into my eye than I should?

It will not usually matter if you put in more drops however your doctor will have prescribed you the optimal dosage for the medication you are using.

If you are unsure whether the drops actually get in your eye, it may be useful to keep the drops in the refrigerator.

You should feel the ‘cold’ of the drops and can be sure they have gone in.

How important is it to put the drops in at exactly the time stated?

It is obviously better to keep to the correct times, but sometimes circumstances make this difficult. In most circumstances, as long as you get the drops in within a few hours on either side of what you normally do, no harm will come.

What if I forget to put my drops in?

Put them in as soon as you remember and do not worry about it unduly. Make a determined effort to use them regularly and without fail.

Set Up a Reminder System

The reminder can be as easy as putting in your eye drops at the same time every day that you perform another routine activity, such as brushing your teeth in the morning and evening. Or you can set phone alarms to remind you to take your eye drops.

Can I take other medicines at the same time as my glaucoma treatment?

Patients with certain types of glaucoma should have advice before taking some types of medications. Always mention to both your general practitioner and your eye specialist all the medications that you are taking and your doctor will advise you.

I have to go to hospital next month for an operation. Do I need to take my eye drops with me or can I give them a break for a while?

It’s very important to take your glaucoma medications with you and to continue with your glaucoma treatment. Make sure your doctors are informed that you take glaucoma medication. You can use your Glaucoma NZ ID card to record your ophthalmologist’s name and the details of your medication.

Sometimes glaucoma treatment gets overlooked because attention is being given to your other problems.

Remind nursing staff if you think your drops have been forgotten.

I am finding it difficult to put in my eye drops, Is there anything available to help me?

There are some devices to help you get your drops in. They are generally available from your eye specialist. Ask at your eye clinic or find out more here



What should you do if one forgets to pack one’s eye drops on a trip overseas?

The short answer to this one is don’t do it! Don’t ever jeopardise your sight by going away without your drops! The Glaucoma NZ ID card has space for recording details of your medication and treatments as well as the phone numbers of your eye health professionals in New Zealand.

If you carry that in your wallet you will have information at hand if you need to seek a replacement prescription while overseas.

Another good idea is to carry a brief summary letter from your ophthalmologist with you when you travel overseas. If you are a frequent traveller why not keep such a letter with your passport, so it travels with you. Who knows, seeing the letter might even serve to remind you to check that your drops are packed before you go.

Glaucoma and Eye Drops

Glaucoma specialist, Dr Sonya Bennett provides an understanding of how lowering the pressure works, talks broadly about eye drops in a simplified way, and discusses the challenges with eye drop treatment for both the patient and the eye specialist.

Eye Drops Do’s and Don’ts

  • Spread your drops out through the day: If a drop is prescribed to be used twice a day, try to space them by 12 hours. If the drop is prescribed three times a day, it should be every eight hours. If you sleep more than eight hours, use the drop on waking, at approximately 2:30 in the afternoon, and again just before sleep.
  • When multiple drops are used in the same eye, it is important to wait at least 5 minutes between drops. Waiting longer is OK but if you put the drops in too close together, the second drop may wash out the first.
  • Close your eye after putting drop-in: the drops work best if you keep your eye closed for around two minutes without blinking. Put pressure on the corner of your eye either by placing your finger in the corner of your eye or holding a tissue on your eye. This helps the solution to be absorbed directly into the eye and will also prevent getting some side effects.
  • Make sure you don’t run out of drops: When glaucoma medicines are prescribed, it is expected that you will use them until your doctor tells you they may be discontinued. If you are running low on drops and need a refill, please telephone your doctor to organise a prescription.

Eye Drop Side Effects

Serious side effects from eye drops are very uncommon but you need to be aware of them.   Less severe problems such as stinging and irritation may be tolerable if the medication is working well, but equally may be unacceptable as glaucoma medications need to be used long term.

The different drops fall into five main categories, which work in slightly different ways: Alpha agonist, Beta blockers, Carbonic anhydrase inhibitors, Cholinergic inhibitors and Prostaglandin analogues. These are also explained in the eye drop side effects fact sheet.

This list does not include all possible side effects from eye drops. If you are concerned by other potential side effects from drops, or if you are having problems with any of the symptoms listed above, please tell your ophthalmologist, optometrist or GP but do not discontinue use until otherwise advised by your health professional.

Betablocker eye drops -Eye drops such as Timolol, Betoptic, Timoptol, Combigan and Dortim can cause:
  • Shortness of breath, wheeziness
  • Tiredness
  • Depression
  • Disturbing bad dreams
  • Impotence, problems with sexual activity
  • Reduced ability to exercise
Brimonidine (also found in Combigan) - Patients taking Brimonidine eye drops sometimes get:
  • Tiredness, drowsiness
  • Dry mouth
  • Conjunctivitis (red, uncomfortable eyes, due to allergy, usually after using the drops for several months)
Prostaglandin eye drops - These include Latanoprost, Travoprost and Bimatoprost and can cause:
  • Red eyes
  • Bruising appearance to the eyelids
  • Long eyelashes
  • Gritty eyes
  • Sunken eyes
Carbonic anhydrase inhibitor eye drops - Users of Trusopt, Azopt & Dortim can experience:
  • Trusopt stings because it has to be a little acidic
  • Allergies similar to the Brimonidine allergy can occur after a number of months
  • Metallic taste


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