Besifloxacin: What it treats and how to use it safely

Ever had red, gritty, sticky eyes and wondered what will actually help? Besifloxacin is an ophthalmic antibiotic used mainly for bacterial conjunctivitis (pink eye). It’s a topical fluoroquinolone, meaning it fights a broad range of bacteria when applied directly to the eye. Because it stays localized, systemic side effects are rare—but you still need to use it the right way.

Besifloxacin usually comes as a 0.6% eye drop. Doctors prescribe it after they suspect or confirm a bacterial infection. Don’t expect it to help viral or allergic pink eye; using antibiotics for the wrong cause just wastes time and can cause resistance.

How to use besifloxacin eye drops

Wash your hands first. Tilt your head back, pull the lower eyelid down to make a small pocket, and squeeze the correct number of drops into that pocket without touching the eye with the bottle tip. After applying, gently close your eye for 1–2 minutes and press the inner corner (near the nose) for 30–60 seconds—this helps keep the medicine in the eye and reduces drainage into your throat.

Follow the exact schedule your prescriber gave you. A common course is one drop in the infected eye every 2–3 hours for a couple of days, then less often, but dosing varies by product and country. Finish the full course even if symptoms improve quickly—stopping early can let bacteria return.

Side effects, precautions, and when to call your doctor

Common side effects are mild: temporary burning, stinging, a bitter taste, or eye irritation right after applying. If you notice severe pain, sudden vision changes, intense redness, swelling, or signs of an allergic reaction (rash, swelling of the face or throat, difficulty breathing), stop using the drops and seek medical care immediately.

Avoid wearing contact lenses while your eye is infected and while using besifloxacin. If you must wear lenses, wait until your doctor clears you. Also, don’t touch the bottle tip to any surface—contaminated drops can cause more harm than good.

Besifloxacin is prescription-only in many places. That’s because a healthcare provider should confirm bacterial infection and check for conditions that need different treatment. If someone else uses your drops, they could make the problem worse.

Wondering about interactions? Because besifloxacin is applied to the eye and not usually absorbed into the bloodstream in meaningful amounts, drug interactions are rare. Still tell your doctor about other eye meds or recent eye surgery.

Quick recap: use besifloxacin only for bacterial eye infections, follow the exact dosing plan, keep the bottle clean, and call your clinician if symptoms get worse or don’t improve in 48–72 hours. Treat the eye right and you’ll likely be back to normal fast.