Besifloxacin belongs to a class of medications called quinolone antibiotics. It is used to treat certain types of eye infections (called bacterial conjunctivitis or "pink eye") that are caused by bacteria. This medication works by killing the bacteria that cause these infections.

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 being given 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 dose for adults and children over 1 year of age is one drop in each affected eye 3 times a day for 7 days.

Before using the eye drops, wash your hands thoroughly. Follow your doctor's or pharmacist's instructions on how to use the eye drops. Before each use, invert the closed bottle and shake once. Do not allow the eye dropper to touch your eyelids, surrounding areas, or any surface. This could contaminate the dropper and lead to an eye infection. Keep the bottle tightly closed when you are not using it.

Use this medication for the full length of time for which your doctor has prescribed. If you stop the medication early, the bacteria may return and be harder to treat.

Many things can affect the dose of a 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 double a 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.

Each mL contains 6 mg of besifloxacin. Nonmedicinal ingredients: benzalkonium chloride 0.01% as a preservative, polycarbophil, mannitol, poloxamer 407, sodium chloride, edetate disodium dihydrate, sodium hydroxide, and water for injection.

Besifloxacin eye drops should not be used by anyone who:

• is allergic to besifloxacin or to any of the ingredients of the medication
• is allergic to other fluoroquinolones (e.g., ciprofloxacin, gemifloxacin, levofloxacin)

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 takes 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 taking 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.

• blurred vision
• eye discharge
• eye irritation
• eye itching
• eye pain

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

• signs of a serious allergic reaction (e.g., abdominal cramps, difficulty breathing, nausea and vomiting, or swelling of the face and throat)

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.

Appropriate use of eye drops: When using this medication, avoid letting the tip of the eye dropper touch the eye, eyelid, fingers, or any other surface. If the tip touches these surfaces, it can become contaminated with bacteria and may worsen your condition. Do not share this product with anyone as it may spread the infection.

Bacterial resistance: Using an antibiotic such as besifloxacin inappropriately may lead to the growth of resistant bacteria that will not be killed by the antibiotic. If this happens, the antibiotic may not work for you in the future. Although you may begin to feel better when you first start taking besifloxacin, you need to take the medication for the full length of time your doctor prescribed to finish ridding your body of the infection and to prevent the growth of resistant bacteria. Antibiotics do not kill viruses, and using them to treat viral infections can lead to the growth of resistant bacteria.

Contact lenses: If you usually wear contact lenses, remove them while you are being treated for bacterial conjunctivitis.

Eye infections: If eye irritation occurs or if the eye infection worsens or has not started to improve in 2 days, you should call your doctor immediately. To minimize the risk of spreading the infection to others, wash your hands frequently and avoid sharing towels, pillowcases, face cloths, or soap with anyone who is infected.

Overgrowth of organisms: Prolonged use of this medication may cause an overgrowth of organisms that this medication does not effectively kill. If your symptoms worsen or do not improve, call your doctor as soon as possible.

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 besifloxacin passes into breast milk. If you are a breast-feeding mother and are taking 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 under 1 year of age.

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. 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. In many cases, interactions are intended or are managed by close monitoring. Speak to your doctor about how any drug interactions are being managed or should be managed.