An antiviral eye drop for herpes-simplex eye infection
Trifluridine
An antiviral eye drop used to treat herpes-simplex infection of the eye (keratitis) affecting the clear front surface.
What is Trifluridine?
Trifluridine is an antiviral medicine used as an eye drop to treat herpes-simplex infection of the eye, known as herpes keratitis, which affects the clear front surface (the cornea). It works by stopping the herpes virus from multiplying so the infection can heal. It is dropped into the affected eye several times a day for a limited period as directed by an eye specialist. The most common effect is stinging or irritation in the eye. It should not be used for longer than advised, as overuse can harm the eye surface. (A separate oral cancer combination called trifluridine-tipiracil exists, but this page is about the antiviral eye drop.)
Education and reference only. This is a plain-language guide to Trifluridine — 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
Trifluridine is an antiviral medicine used in the form of eye drops to treat infection of the eye caused by the herpes-simplex virus, a condition called herpes keratitis. This infection affects the cornea, the clear front part of the eye, and can damage vision if not treated. The drops are placed directly into the affected eye to act where the infection is. It is used under the care of an eye specialist (an optometrist or ophthalmologist) for a defined period. It is important to know that a completely separate medicine, an oral combination called trifluridine-tipiracil used in cancer, shares part of the name, but this page describes the antiviral eye drop.
How it works
Herpes keratitis happens when the herpes-simplex virus infects and multiplies in the cornea, the clear front of the eye. Trifluridine works by interfering with the virus's ability to copy its genetic material, so it cannot multiply and the infection is brought under control, allowing the eye to heal. Because it works only where it is applied, it is given as frequent drops into the affected eye while the infection is active. It is used for a limited time, because using it for too long can itself irritate or damage the surface of the eye.
Company & origin
Originated / developed by: Specialist manufacturers.
An antiviral medicine used as an eye drop to treat herpes-simplex infection of the front of the eye.
Practical use
How to take Trifluridine
General, dose-free guidance — always follow your prescriber's and the leaflet's specific instructions.
- Put the drops into the affected eye as often as your eye specialist directs while the infection is active.
- Do not use the drops for longer than advised, as overuse can harm the surface of the eye.
- A brief sting or irritation when the drop goes in is common and usually settles quickly.
- Avoid wearing contact lenses during an active eye infection unless your specialist tells you otherwise.
- Attend your follow-up eye appointments so healing can be checked.
Weighing it up
Advantages & disadvantages of Trifluridine
Advantages
- An effective antiviral treatment placed directly where the eye infection is.
- Helps the cornea heal and protects sight when herpes keratitis is treated promptly.
- Acts locally in the eye rather than throughout the body.
Disadvantages
- Commonly causes local stinging or irritation when the drops are put in.
- Must not be used for longer than advised, as overuse can damage the eye surface.
- Needs frequent dosing and regular review by an eye specialist.
Practical use
Good to know
The most common problem with trifluridine drops is local stinging, burning or irritation in the eye when they are put in, which usually settles. A key safety point is not to use the drops for longer than your eye specialist advises: using them beyond the recommended period can cause harm to the surface of the eye rather than help it. It is important to use the drops as often as directed during the active infection, as missing doses can let the virus carry on multiplying. You should not wear contact lenses while you have an active eye infection unless your specialist says otherwise. Be sure not to confuse this antiviral eye drop with the oral cancer combination trifluridine-tipiracil, which is an entirely different medicine used in a different way.
Who should not take it / use with caution
- People who have had a serious allergic reaction to trifluridine should not use it.
- It is used with care in pregnancy and breastfeeding, on specialist advice.
- It should only be used under the supervision of an eye specialist who confirms the diagnosis.
Monitoring
- Regular eye-specialist review to check the cornea is healing.
- Watching for irritation or surface damage from prolonged use.
- Stopping the drops at the recommended point rather than continuing them indefinitely.
Side effects
- Stinging, burning or irritation in the eye when the drops are used.
- Redness, watering or a gritty feeling in the treated eye.
- With prolonged use, harm to the surface of the eye, which is why it is used only for a limited time.
Key interactions
- There are few well-established interactions, but tell your specialist about any other eye drops you use.
- If you use more than one type of eye drop, leave time between them so each works properly.
- Tell your specialist about all your medicines and any eye conditions.
Available as: Eye drops applied to the affected eye.
Answers
Trifluridine: frequently asked questions
What is trifluridine used for?
As an eye drop, it is used to treat herpes-simplex infection of the eye (herpes keratitis), which affects the clear front surface of the eye.
Why does the drop sting?
Local stinging or irritation when the drop goes in is the most common effect and usually settles quickly after putting it in.
Can I use it for as long as I like?
No. It should not be used for longer than your eye specialist advises, because using it for too long can damage the surface of the eye.
Is this the same as the cancer medicine?
No. A separate oral cancer combination called trifluridine-tipiracil exists, but this page is about the antiviral eye drop, which is a different medicine used in a different way.
Can I wear contact lenses?
It is best not to wear contact lenses during an active eye infection unless your specialist tells you it is safe to do so.
The wider class
About Antiviral (herpes-simplex eye infection)
Trifluridine belongs to the antiviral (herpes-simplex eye infection) 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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