Trifluridine belongs to a group of medications known as antivirals. It is used to treat certain eye infections caused by herpes simplex virus types 1 and 2. It works by killing the virus that causes the infection.

This medication may be available under multiple brand names and/or in several different forms. Any specific brand name of this medication may not be available in all of the forms or approved for all of the conditions discussed here. As well, some forms of this medication may not be used for all of the conditions discussed here.

Your doctor may have suggested this medication for conditions other than those listed in these drug information articles. If you have not discussed this with your doctor or are not sure why you are using this medication, speak to your doctor. Do not stop using this medication without consulting your doctor.

Do not give this medication to anyone else, even if they have the same symptoms as you do. It can be harmful for people to use this medication if their doctor has not prescribed it.

The usual recommended adult dose of trifluridine eye drops is 1 drop into the affected eye(s) (on the cornea) every 2 hours while awake (up to a maximum of 9 drops per day). This dose is continued until the eye lesion heals over, usually within 7 to 14 days. Then, the usual dose is 1 drop into the affected eye(s) every 4 hours (up to a maximum of 5 drops per day) while awake for 7 days. The medication should not be used for longer than 21 days. If no improvement is seen in 7 days, or if the lesion has not healed within 14 days, see your doctor.

Before instilling these eye drops, wash your hands thoroughly with soap and warm water. To avoid contaminating the eye drops, do not touch the tip of the dropper to any surface, including your eye or finger.

Many things can affect the dose of medication that a person needs, such as body weight, other medical conditions, and other medications. If your doctor has recommended a dose different from the ones listed here, do not change the way that you are using the medication without consulting your doctor.

It is important to use this medication exactly as prescribed by your doctor. If you miss a dose, instill it as soon as possible and continue with your regular schedule. If it is almost time for your next dose, skip the missed dose and continue with your regular dosing schedule. Do not instill a double dose to make up for a missed one. If you are not sure what to do after missing a dose, contact your doctor or pharmacist for advice.

Store this medication in the refrigerator at 2°C to 8°C (do not allow to freeze), protect it from light, and keep it out of the reach of children.

Trifluridine should not be used by anyone who is allergic to trifluridine or to any of the ingredients of the medication.

Many medications can cause side effects. A side effect is an unwanted response to a medication when it is taken in normal doses. Side effects can be mild or severe, temporary or permanent. The side effects listed below are not experienced by everyone who uses this medication. If you are concerned about side effects, discuss the risks and benefits of this medication with your doctor.

The following side effects have been reported by at least 1% of people using this medication. Many of these side effects can be managed, and some may go away on their own over time.

Contact your doctor if you experience these side effects and they are severe or bothersome. Your pharmacist may be able to advise you on managing side effects.

• burning or stinging
• mild irritation of the eye
• swelling and redness of the eyelid

Although most of the side effects listed below don't happen very often, they could lead to serious problems if you do not check with your doctor or seek medical attention

Check with your doctor as soon as possible if any of the following side effects occur:

• itching, redness, swelling, or other sign of irritation not present before use of this medication

Stop taking the medication and seek immediate medical attention if any of the following occur:

• signs of an allergic reaction (e.g., skin itching, rash, redness, swelling, or hives)

Some people may experience side effects other than those listed. Check with your doctor if you notice any symptom that worries you while you are taking this medication.

Before you begin using a medication, be sure to inform your doctor of any medical conditions or allergies you may have, any medications you are taking, whether you are pregnant or breast-feeding, and any other significant facts about your health. These factors may affect how you should use this medication

Pregnancy: This medication should not be used during pregnancy unless the benefits outweigh the risks. If you become pregnant while using this medication, contact your doctor immediately.

Breast-feeding: It is not known if trifluridine passes into breast milk. If you are a breast-feeding mother and are using this medication, it may affect your baby. Talk to your doctor about whether you should continue breast-feeding.

Children: The safety and effectiveness of using this medication have not been established for children.

There may be an interaction between trifluridine and any of the following:

• other eye drops

If you are using any of these medications, speak with your doctor or pharmacist. Depending on your specific circumstances, your doctor may want you to:

• stop taking one of the medications,
• change one of the medications to another,
• change how you are taking one or both of the medications, or
• leave everything as is.

An interaction between two medications does not always mean that you must stop taking one of them. Speak to your doctor about how any drug interactions are being managed or should be managed.

Medications other than those listed above may interact with this medication. Tell your doctor or prescriber about all prescription, over-the-counter (non-prescription), and herbal medications that you are taking. Also tell them about any supplements you take. Since caffeine, alcohol, the nicotine from cigarettes, or street drugs can affect the action of many medications, you should let your prescriber know if you use them.