Antihistamine eye drops for allergic conjunctivitis
Emedastine
Antihistamine eye drops used to relieve the itchy, watery, red eyes of allergic conjunctivitis.
What is Emedastine?
Emedastine is an antihistamine given as eye drops to treat allergic conjunctivitis, the itchy, red, watery eyes caused by allergies such as hay fever. It works by blocking histamine, the chemical released during an allergic reaction, so the eyes feel less itchy and irritated. The most common effects are local, such as brief stinging when the drops go in and short-lived blurred vision. It is for the eyes only and is not a treatment for eye infections.
Education and reference only. This is a plain-language guide to Emedastine — it deliberately contains no doses. Doses depend on the person, the brand and the reason for treatment, and belong with your prescriber. Always check the BNF, the product labelling (SmPC) and follow medical advice.
What it is
Emedastine is an antihistamine that comes as eye drops, used to relieve allergic conjunctivitis. This is the eye allergy that causes itching, redness, watering and a gritty feeling, often as part of hay fever or in response to allergens such as pollen, dust or pet dander. The drops act directly on the eye, treating the allergy symptoms where they happen. They are used for allergic eye symptoms, not for infections of the eye, which need different treatment.
How it works
When the eye comes into contact with something a person is allergic to, the body releases histamine, which makes the eye itch, redden, water and swell. Emedastine blocks the histamine receptors in the eye, so histamine cannot trigger these symptoms as strongly, and the eye feels more comfortable. Because the drops act locally, they relieve the eye symptoms fairly quickly and need to be used regularly while the allergy trigger is around. They calm the allergic reaction rather than removing whatever is causing it.
Company & origin
Originated / developed by: Specialist manufacturer.
An antihistamine eye drop used in the UK to relieve the itchy, watery, red eyes of allergic conjunctivitis.
Practical use
How to take Emedastine
General, dose-free guidance — always follow your prescriber's and the leaflet's specific instructions.
- Put the drops into the affected eye or eyes as directed, washing your hands first.
- Avoid touching the dropper tip to your eye or anything else, to keep the drops clean.
- Wait until any blurring has cleared before driving or doing anything needing sharp vision.
- If you wear contact lenses, take them out before using the drops and wait a while before putting them back.
- Use them regularly while you are exposed to the allergy trigger rather than only now and then.
Weighing it up
Advantages & disadvantages of Emedastine
Advantages
- Relieves the itchy, watery, red eyes of allergic conjunctivitis where the symptoms happen.
- Works fairly quickly and is simple to use as eye drops.
- Acts mainly on the eye, so it is less likely to cause whole-body antihistamine effects such as drowsiness.
Disadvantages
- Can cause brief stinging or discomfort when the drops go in.
- May blur vision for a short time after use.
- Treats the allergy symptoms but does not remove what is causing the allergy.
Practical use
Good to know
The handiest thing to know is that emedastine works where the symptoms are, so it tends to ease itchy, watery, red eyes fairly quickly. A brief sting or mild discomfort when the drops go in is common and usually settles in moments, and your vision may be blurred for a short time straight afterwards, so it is best not to drive until your sight is clear. If you wear contact lenses, it is usually advised to take them out before putting the drops in and to wait a little while before putting them back, as some drops contain a preservative that lenses can hold onto. Using the drops regularly during the allergy season works better than now and then, and reducing contact with the trigger, where possible, helps too.
Who should not take it / use with caution
- People who have had a serious allergic reaction to emedastine should not use it.
- It is used with caution in pregnancy and breastfeeding, on medical advice.
- Suitability in young children should be checked with a doctor or pharmacist.
Monitoring
- Reviewing whether the eye symptoms are improving with regular use.
- Watching for ongoing irritation or any reaction to the drops.
- Seeking advice if symptoms do not improve or the eye becomes painful or very red.
Side effects
- Brief stinging, burning or discomfort when the drops go in.
- Short-lived blurred vision straight after using the drops.
- Dryness, redness or a feeling of something in the eye in some people.
- Rarely, an allergic reaction to the drops themselves.
Key interactions
- There are few important interactions because the drops act mainly on the eye.
- If you use other eye drops, leave a gap between them so each has time to work.
- Tell your pharmacist about other medicines and eye products you use.
Available as: Eye drops.
Answers
Emedastine: frequently asked questions
What is emedastine used for?
It is an antihistamine eye drop used to relieve allergic conjunctivitis, the itchy, red, watery eyes caused by allergies such as hay fever.
Why do the drops sting at first?
A brief sting or mild discomfort when the drops go in is common and usually settles within moments; your vision may also blur for a short time.
Can I drive after using them?
Wait until any blurring has cleared before driving or doing anything that needs sharp vision.
Can I use them with contact lenses?
It is usually advised to take your lenses out before using the drops and wait a while before putting them back, as the preservative can be held by lenses.
Do they treat eye infections?
No. Emedastine treats allergy symptoms in the eye, not infections, which need different treatment, so see a professional if you suspect an infection.
The wider class
About Antihistamine eye drops
Emedastine belongs to the antihistamine eye drops class. For how the class as a whole works, its shared safety principles and monitoring, see the full guide.
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Authoritative sources
- BNF
- NICE CKS
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