About dorzolamide eye drops
|Type of medicine||A carbonic anhydrase inhibitor|
|Used for||Raised eye pressure, such as in glaucoma|
|Also called||Trusopt®, Dorzant®
Also Cosopt® (this contains dorzolamide in combination with timolol)
|Available as||Eye drops (these contain a preservative), and single-dose units (these are preservative-free)|
An increase in pressure within your eye can lead to damage to the optic nerve at the back of your eye. When this occurs it is called glaucoma. Glaucoma can lead to a loss of vision if it is not treated. If you have an increased pressure within your eye but without any damage to the optic nerve, this is called ocular hypertension. People with ocular hypertension have an increased risk of later developing glaucoma.Treatment with eye drops such as dorzolamide helps to reduce eye pressure in people with ocular hypertension, and to prevent further eye damage in people with glaucoma.
Dorzolamide works by blocking the action of an enzyme called carbonic anhydrase. Blocking this enzyme reduces the amount of fluid that you make in the front part of your eye (called aqueous humour), and this helps to lower the pressure within your eye.
Sometimes, more than one type of eye drop is needed to keep the pressure in the eye low. If this is the case for you, you may be asked to use two different eye drops, or you may be given drops which combine more than one type. Dorzolamide is available as a combination eye drop with a beta-blocker called timolol (which also helps to reduce the amount of fluid your eye makes).
Before using dorzolamide
Some medicines are not suitable for people with certain conditions, and sometimes a medicine may only be used if extra care is taken. For these reasons, before you start using dorzolamide eye drops, it is important that your doctor or pharmacist knows:
- If you are pregnant, trying for a baby or breast-feeding.
- If you have liver or kidney problems (especially if you have ever had kidney stones).
- If you wear soft contact lenses.
- If you are taking other medicines, including those available to buy without a prescription, herbal and complementary medicines.
- If you have ever had an allergic reaction to any medicine. It is particularly important that you tell your doctor if you have ever had a bad reaction to a type of medicine known as a 'sulfonamide'. Sulfonamide medicines are used for infections, in diabetes, and as diuretics ('water tablets').
How to use dorzolamide eye drops
- Wash your hands before you use the drops.
- Remove the cap (or the tip of the unit if you are using a single-dose unit).
- Tilt your head back a little and pull the lower lid of your eye out to form a pocket.
- Hold the bottle (or single-dose unit) upside down near to your eye. Try not to touch your eye as you do this.
- Apply enough pressure to release one drop into your eye.
- 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.
- Repeat the process in your other eye if you have been told to use the drops in both eyes.
- Replace the cap (or if you are using the single-dose unit, throw it away).
Getting the most from your treatment
- Before you start using these eye drops, read the manufacturer's printed information leaflet from the pack. The leaflet will give you more information about the eye drops and a full list of possible side-effects from using them.
- Use one drop into the eye (or eyes) affected. These drops are used two or three times each day depending on whether you are also using other drops. Your doctor will tell you how many times a day is right for you and your dose will also be on the label of your pack.
- Remember to use these drops at regular intervals and try not to miss any doses. If you forget to use the drops, apply them as soon as you remember unless it is nearly time for your next dose, in which case just use the drops when they are next due. Do not double up to make up for a missed dose.
- Take care not to touch the tip of the dropper with your eye, fingers, or any other surface. This is to prevent the drops from becoming contaminated.
- If you are using any other eye drops, leave 5-10 minutes between applying each one.
- When first put in, eye drops may sometimes cause blurred vision. If this happens, it should quickly clear. Make sure you can see clearly before you drive, or use tools or machines.
- Do not wear soft contact lenses unless your doctor has advised you otherwise. This is because bottles of eye drops contain preservatives which can affect soft contact lenses. The single-dose units do not contain a preservative.
- Keep your regular appointments with your doctor so that your progress can be checked.
- If you are having an operation or any medical treatment, remember to tell the person carrying out the treatment that you are using these eye drops.
Can dorzolamide eye drops cause problems?
Along with their useful effects, most medicines can cause unwanted side-effects although not everyone experiences them. These usually improve as your body adjusts to the new medicine, but speak with your doctor or pharmacist if any of the following side-effects continue or become troublesome.
|Common dorzolamide side-effects - these affect around 1 in 10 people who use these eye drops||What can I do if I experience this?|
|Burning or stinging when the drops are first put in||This should quickly ease. If it continues, or if your eye becomes red or inflamed, speak with your doctor as soon as possible|
|Headache||Ask your pharmacist to recommend a suitable painkiller|
|A bitter taste in your mouth, or feelings of sickness||Make sure you press gently on the side of your nose (where the corner of your eye meets your nose) for a minute or so after you have used the drops. You can also try chewing sugar-free gum or sucking sugar-free sweets to take the taste away|
|Feeling tired||If this becomes troublesome, speak with your doctor|
Bottles of eye drops contain preservatives which some people can develop an allergic reaction to. If your eye becomes red or inflamed after using the drops, or if you develop any swelling of your mouth or face, stop using the drops and contact your doctor for advice straightaway.
How to store dorzolamide
- Keep all medicines out of the reach and sight of children.
- Store in a cool, dry place, away from direct heat and light.
- Bottles of eye drops only keep for four weeks once the bottle has been opened, so do not use the drops if the bottle has been open for longer than this. This will help to prevent the risk of eye infections.
- Single-dose units should be used immediately the unit is opened. Do not store or re-use opened units for subsequent doses. This is because the units do not contain any preservative.
Important information about all medicines
Further reading & references
- British National Formulary; 63rd Edition (Mar 2012) British Medical Association and Royal Pharmaceutical Society of Great Britain, London
- Manufacturer's PIL, Dorzolamide 20 mg/ml eye drops, solution; Manufacturer's PIL, Dorzolamide 20 mg/ml eye drops, solution, Beacon Pharmaceuticals, The electronic Medicines Compendium. Dated December 2010.
- Manufacturer's PIL, Trusopt® Preservative-free 20 mg/ml eye drops solution, single-dose container; Manufacturer's PIL, Trusopt® Preservative-free 20 mg/ml eye drops solution, single-dose container, Merck Sharp & Dohme Limited, The electronic Medicines Compendium. Dated September 2010.
|Original Author: Helen Allen||Current Version: Helen Allen||Peer Reviewer: Prof Cathy Jackson|
|Last Checked: 18/05/2012||Document ID: 1413 Version: 23||© EMIS|
Disclaimer: This article is for information only and should not be used for the diagnosis or treatment of medical conditions. EMIS has used all reasonable care in compiling the information but make no warranty as to its accuracy. Consult a doctor or other health care professional for diagnosis and treatment of medical conditions. For details see our conditions.